Molecular Genetic Study of Sexual Orientation
 
 
 
 
 

 

 
FAQs
 

This FAQ provides background information about the “Molecular Genetic Study of Sexual Orientation,” which is under the direction of Dr. Alan R. Sanders. The FAQ also describes some background on sexual orientation research, especially with regards to gay men, and a discussion of some of the ethical, legal, and social implications of sexual orientation research.

This FAQ was prepared in consultation with a community advisory board. For further information about this FAQ, please contact Dr. Timothy F. Murphy, University of Illinois at Chicago College of Medicine (tmurphy@uic.edu). Dr. Murphy is a consultant to this project and the organizer of the advisory board.


   
I. ABOUT THIS STUDY
     
  A. What is the purpose of this study?
  B. How will the volunteers be recruited?
  C. Who is eligible to volunteer for the study?
  D. Who is NOT eligible to volunteer for the study?
  E. Why are lesbians not eligible for the study?
  F. What will the study involve for the volunteers?
  G. Are there any risks to the volunteers?
  H. Are there any benefits to the volunteers?
  I. Who is carrying out the study?
  J. Who is paying for it?
  K. How will volunteers learn about the findings?
  L. Who can offer more information about the study?
  M. How is community input being included in this study?
     
II. ABOUT HOMOSEXUALITY
     
  A. What is homosexuality?
  B. How common is homosexuality?
  C. What is known about the development of homosexuality?
  D. Do genes contribute to homosexuality?
     
III. ETHICAL ASPECTS OF SEXUAL ORIENTATION RESEARCH
     
  A. Why do researchers study the development of homosexuality?
  B. Is the study of male homosexuality different from the study of female homosexuality?
  C. Why is the study of homosexuality controversial?
  D.

Do scientists study homosexuality in order to find a ‘cure’ or ‘treatment’?

  E. Will the study of homosexuality lead people to believe that it is an illness or disorder?
  F. Will future research develop a ‘test’ that makes it possible to discover someone’s sexual orientation?
  G. Will research give parents the ability to control the sexual orientation of their children in any way?
  H. Will the biological study of homosexuality lead to fewer homosexual people in the world?
     
IV. LEGAL ASPECTS OF SEXUAL ORIENTATION RESEARCH
     
  A. What is the legal status of homosexuality in the United States?
  B. Will research influence the legal status of homosexuality?
  C. Will the biological study of homosexuality lead to new laws?
     
REFERENCES
     
FURTHER READING
     
RESOURCES FOR THE GAY COMMUNITY
     

   
I. ABOUT THIS STUDY
     
  A. What is the purpose of this study?
     
   

In 2003, the N.I.H. funded Dr. Alan R. Sanders, a psychiatrist at NorthShore University HealthSystem Research Institute to conduct a five-year study of approximately 1,000 pairs of gay brothers, along with any other available brothers and parents from families recruited from the United States, Canada, the United Kingdom, Ireland, and Australia, i.e., mainly English speaking countries since the materials such as the web site, consent form, and questionnaire are in English.

The purpose of this study is to see whether gay brothers on average share genetic regions inherited from their parents. When studying a trait, such as sexual orientation, with genetic techniques it is much more efficient to focus on the less common variant; hence, we are studying families with gay brothers to learn more about the development of male sexual orientation. This study will shed light on the role of genetics in the development of sexual orientation of human males.

Some research indicates that some very ‘feminine’ boys seem to become homosexual more frequently than other boys (reviewed in [1]). The same seems to hold true of some very ‘masculine’ girls. It is also true that many children who become homosexual adults behave just like other members of their own gender. However, it is not our intention to perpetuate stereotypes, or to imply that all gay men are or were 'feminine'. Rather, our purpose is to understand what impact childhood 'masculinity' and 'femininity' may have on the adult lives of men who are attracted to other men. In order to explore these observations further, this study will ask participating brothers about their recollections of their childhood behaviors such as play activities, relationships with others, and so on.

     
  B. How will the volunteers be recruited?
     
    Volunteers are being recruited through ads in gay news media and through recruitment booths at Pride and neighborhood festivals in major metropolitan areas such as Chicago, Los Angeles, Toronto, Seattle, etc., in addition to through this website, from the US, Canada, the United Kingdom, Ireland, and Australia. The researchers also are contacting volunteers through recruitment booths at conferences and professional meetings, and through various organizations. When given permission to do so by the volunteers themselves, recruiters will contact brothers and family members directly.
     
  C. Who is eligible to volunteer for the study?
     
    Gay men with at least one living gay brother, that is at least two gay brothers, are eligible to participate, as are their available and willing other brothers and parents regardless of their sexual orientation. However, other family members need not participate; as long as two gay brothers are willing to participate, they may be involved in the study. The gay brothers may be full brothers (share both biological parents), half brothers (share one biological parent), or fraternal (dizygotic) twins. Subjects may participate regardless of HIV status or any other medical condition.
     
  D. Who is NOT eligible to volunteer for the study?
     
    Identical (monozygotic) twins are not eligible since it is already known that their DNA (genetic material) is the same. However, we know of other researchers studying identical twins; if such a family is interested in potentially participating in a twin study, we can provide researcher contact information. Individuals below the age of 18 are not eligible due to more uncertainty as to their actual sexual orientation as adults.
     
  E. Why are lesbians not eligible for the study?
     
   

There is some evidence to suggest that genetics may play a role in female sexual orientation [2, 3]. However, there is no evidence suggesting that a particular genetic region is involved in the sexual orientation of women, as there is for men [4]. In fact, researchers have shown that a particular genetic region that might influence sexual orientation in males shows no evidence of that effect in women [5]. Family and twin studies have also shown indications that male and female sexual orientation may have different genetic influences from each other [6].

Due to a larger literature at the time suggesting significant genetic contributions to male sexual orientation, we chose to focus this study on males. Similar studies are anticipated in the future, but we are unaware of any studies with women at the present time.

     
  F. What will the study involve for the volunteers?
     
   

This study involves two main components.

People in the study will provide a DNA sample (blood or saliva sample). This sample is used to extract DNA for the genetic part of the research study. We are not studying other aspects of the blood or saliva, such as a person’s HIV status.

The brother volunteers will also complete questionnaires about their sexual interests and experiences, memories of their childhood and adult gender related behavior, demographic characteristics, health and medical history, and personal and family history.

The gay brothers will also supply contact information about their other brothers and parents, if those family members have indicated their interest in potentially volunteering for the study.

More information is available in the brochure available on-line. A full description of the volunteer’s activities in this study are contained in a document that will be given to them and discussed with them, if they have any questions, before they agree to participate. This document is called the consent form.

     
  G. Are there any risks to the volunteers?
     
   

Taking blood samples for this study involves the same risks involved with any blood draw, such as bruising or minor infection. We use experienced phlebotomists (blood drawers) to minimize these risks as far as possible. Taking saliva samples does not entail any of the above risks of a routine blood draw.

Volunteers may also possibly experience moments of psychological discomfort while completing the questionnaire, for example questions about childhood may prompt them to recall an unhappy time.

We have taken many safeguards to protect volunteers’ confidentiality. A research number will be assigned to volunteers, and their names will not be used. Volunteers will not be personally identified in any reports from this study. The results from the analysis of volunteers’ DNA or other information will not be released or shared in any way with relatives, with insurance companies, or any one not directly involved in the research. No volunteers’ names will ever be published as participants in the study.

We have obtained a Certificate of Confidentiality from the Federal Government (http://grants.nih.gov/grants/policy/coc/) for this study. This certificate entitles us to protect all participants’ names from government and legal agencies.

The volunteers retain the right to withdraw from the study for any reason.

     
  H. Are there any benefits to the volunteers?
     
   

Volunteers are reimbursed for the time and expenses involved in offering a DNA sample (blood or saliva) and completing a questionnaire.

There are no direct therapeutic benefits for the volunteers.

Volunteers may have the satisfaction of knowing that they are helping improve scientific understanding of the development of sexual orientation and genetic contributions to that process.

     
  I. Who is carrying out the study?
     
    Dr. Alan R. Sanders is leading a team that is recruiting families for the study. Dr. Sanders is a psychiatrist who studies behavioral genetics. He is an Associate Professor at Northwestern University and the Director of the Behavior Genetics Unit at NorthShore University HealthSystem Research Institute. His research team includes a number of scientists from several academic institutions in the Chicago area, as detailed in the brochure available on-line.
     
  J. Who is paying for it?
     
    This study is funded by the U.S. National Institutes of Health from the NICHD (National Institute for Child Health and Human Development; grant number R01 HD041563). Funding runs from 2003-2008.
     
  K. How will volunteers learn about the findings?
     
    The volunteers will not be directly informed about the findings of the study as far as any information about them as individuals or families. It will take several years to collect and analyze the data from this study. The researchers will publish their findings in scientific journals, and their findings may be reported on in the news media. In the meantime, the study website will provide updates and links to papers and presentations associated with this study.
     
  L. Who can offer more information about the study?
     
    If you think you are eligible for the study and would like to participate or if you would like further information about other aspects of the study, please contact us through the toll-free number, 866-364-7571. Refer to our contacts page for further information.
     
  M. How is community input being included in this study?
     
    We have assembled a community advisory board, consisting of researchers, educators, and clinicians who are knowledgeable about the background and issues pertinent to the gay and lesbian community. The advisory board meets several times a year with the research team to discuss and advise on all of the publicity, recruitment, and community education. We also continue to incorporate suggestions from research participants and other interested parties.
     
II. ABOUT HOMOSEXUALITY
     
  A. What is homosexuality?
     
   

Homosexuality refers to erotic attraction and behavior between people of the same sex: males sexually attracted to males, males having sex with males, females sexually attracted to other females, and females having sex with other females. Homosexuality can be expressed in a variety of psychological, behavioral, and cultural ways. We, like many others, often refer to homosexual males as gay men, and homosexual females as lesbians.

Like other sexual interests, homosexual interests in human beings are variable. For example, some adolescents may have sexual interest in their same-sex peers but never act on those desires. Other adolescents may have sex with members of their same sex but move toward opposite-sex partners later on. Some people may experience homosexual interests only later in life. Some people experience homosexual interests throughout their lives, while others (most people) never seem to have any sexual interest in members of their own sex. We are studying a stable, long-term trait. This study will therefore not enroll any adolescents. Volunteers must be at least 18 years old for our study.

     
  B. How common is homosexuality?
     
   

Homosexuality occurs to some extent in every known human society, though its exact extent is a matter of debate.

Some researchers believe that all people are capable of some degree of homosexual desire and behavior [7]. If they are correct, then variability in sexual orientation is a universal human trait, as a sexual capacity even if it is never strongly experienced or acted on.

Other researchers study the way people describe their own erotic attractions, their behavior, and the way they describe their identities in order to measure the extent of homosexuality in a given population. One team of researchers studying people that way in the United States reported that 2.8% of their male subjects and 1.4% of the female subjects identified themselves as having a homosexual or bisexual identity [8]. They noted, however, that a considerable number of men and women who report themselves as having a homosexual identity also say that they have had heterosexual sex at some point in their lives as well [8]. This same research team found that the numbers of people who have had sex with members of their own sex are larger than the number of people who claim a homosexual identity: more than 9% of the men and 4% of the women [8]. It is safe to say that there are not always fixed boundaries between homosexuality and heterosexuality.

In some settings, the expression of homosexual interest and behavior is socially accepted and – for that reason – appears more common. The social invisibility of homosexuality in other settings does not mean, however, that there is no homosexuality at all in a particular culture. In societies where there is strong disapproval of homosexuality, measuring the prevalence of homosexual desire, behavior, and identities can be very difficult.

     
  C. What is known about the development of homosexuality?
     
   

At the present time, there is no uniformly accepted theory of why some men and some women develop a sexual orientation that is more or less exclusively focused on members of their own sex.

Many researchers in the 19th century believed that homosexuality was a mental illness or pathology. They wanted an explanation of homosexuality that would help them prevent and treat what they considered a sexual disorder. Since the 1970s, most professional medical and psychological organizations around the world have rejected the view that homosexuality is a mental disorder [9], and much of the early research on homosexuality is not taken seriously today.

Still, it is an interesting question why homosexuality comes to the fore in some people but not in others. The psychiatrist Sigmund Freud believed that there was a degree of bisexuality in all human beings. He believed it was worthwhile to discover how individual psychological development occurred: why people develop their specific sexual interests and behaviors [10], for homosexuality and heterosexuality alike. Most contemporary researchers share this same perspective.

Most contemporary researchers believe that sexual orientation – the general disposition of people toward homosexuality, bisexuality, or heterosexuality – is the result of both biological factors and psychological experiences. Most researchers do not believe that sexual orientation is the result of nature (biology, including genetics) alone or nurture (environment) alone. What researchers want to know is how specific factors in biology and psychology interact to guide sexual development. These researchers therefore look for biological and psychological differences between homosexual and heterosexual people, both men and women.

For example, one researcher reported differences between homosexual men and heterosexual men in very small structures in the part of the brain known to influence sexual desire [11]. Another research team noted that homosexual men are likely to have more leftward asymmetric finger skin ridges on their hands than heterosexual men [12]. Another researcher reported that homosexual men are likely to have larger length differences between their ring and index fingers than heterosexual men do [13]. While most of the biological research of homosexuality involves males, some research has been done with females. One research team reported that homosexual women are less sensitive to very soft sounds than heterosexual women [14]. Another study of women showed that homosexual women show blink responses more like those of men than of heterosexual women [15]. Studies such as these are at various stages of being confirmed by other investigators; when findings are independently reproduced one can have much more confidence in them.

These studies are designed to show a correlation between a trait and sexual orientation. This is not the same as showing that a trait causes sexual orientation. What is not yet known is whether these traits and sexual orientation have a common origin in genetics or other biological influences on development, though these hypotheses are being pursued. In any case, these lines of research are suggestive rather than definitive. Among other factors, it is these and other uncertainties that prompt continued research.

     
  D. Do genes contribute to homosexuality?
     
   

In the 19th century, some researchers believed that some people were ‘born’ homosexual and that other people ‘acquired’ homosexuality [16, 17]. These researchers speculated that genes could be involved in some homosexuality, while other people moved toward homosexuality because of psychological and social reasons. These early genetic theories were not based on hard scientific evidence since researchers at that time lacked the tools for direct genetic analysis that are available today. Mostly, the evidence for genes playing a role in sexual orientation was indirect.

In the 1950s, one U.S. researcher offered some reason for thinking homosexuality might have a genetic basis: he showed that identical twins (monozygotic twins, who share the same DNA as each other) shared a homosexual orientation at a high rate [18]. Even so, this evidence was not definitive. Some commentators noted that the twins grew up in the same environments, which means that their sexual orientation might have another cause than their shared genetics.

In the 1970s, an evolutionary biologist addressed a key problem in genetic theories of homosexuality: if homosexuality is genetic, how is it passed from one generation to the next? After all, sexual acts between men (or between women) do not produce children. This researcher showed that genes for homosexuality could move successfully from one generation to the next through groups, rather than individuals [19]. In other words, genes for homosexuality could be only occasionally expressed and produce homosexual men (and women) only from time to time. Like other genetic theories, this theory has attracted critics who believe there is not enough evidence to show that this is actually true [20].

In the 1990s, several research teams found interesting genetic aspects to sexual orientation. Researchers found that in a study of brothers, if one male sibling was homosexual, the chance his identical (monozygotic) twin would be homosexual was 52%; the chance that his fraternal (dizygotic) twin would be homosexual was 22%; the chance that his adopted brother would be homosexual was 11% [21]. The researchers conducted a companion study that showed if one female sibling was homosexual, the chance that her identical (monozygotic) twin would be homosexual was 48%; the chance that her fraternal (dizygotic) twin would be homosexual was 16%; while the chance that an adopted sister would be homosexual was 6% [3]. The researchers believe that these graduated effects establish some degree of genetic contribution to homosexuality.

In 1993, an NIH (National Institutes of Health) research team led by Dr. Dean H. Hamer conducted a pedigree study that showed a matrilineal pattern of cross-generational male homosexuality, i.e., evidence that this trait to some degree is inherited through the maternal line [4]. Through genetic linkage analysis of 40 pairs of gay brothers, that study also showed that a particular genetic region on the X chromosome (Xq28) was shared between homosexual brothers at a significantly higher rate than between homosexual men and their heterosexual brothers. The X chromosome has maternal (not paternal) inheritance in men. Contrary to popular perception, this study did not discover a ‘gay gene.’ The genetic region in question is large enough to contain many genes. It is also true that the shared region might involve some other trait that the gay brothers share. A companion study by the same research group of 36 pairs of lesbian sisters found no clear genetic or environmental patterns in the sexual orientation of females, though this study’s findings in 33 pairs of gay brothers supported the previous Xq28 finding in men [5]. In 1999, an independent team of Canadian researchers reported their study of 52 pairs of gay brothers, which provided no evidence of replication for Xq28 markers [22].

In 2005, Dr. Hamer's team of researchers reported a genome scan -- which surveys the entire genetic make-up of a person -- and identified other areas that might be involved in male homosexuality [23]. This study suggested that there might be a variety of genetic influences – not just one – that contribute to homosexuality in males. This study was performed on two previously collected samples – 40 pairs of gay brothers [4] and 33 pairs of gay brothers [5] – added to 73 additional (newly studied) pairs of gay brothers [23]. This is the largest completed genetic linkage study to date and the only one performed on the entire genome, both notable improvements. The strongest finding (which involved chromosome 7q36) approached but did not quite reach statistical significance, that is, this finding could have occurred just by chance. This study did not provide further support for a gene on Xq28 contributing to sexual orientation in the 73 new families.

In 2003, the National Institutes of Health gave financial support to Dr. Alan R. Sanders to initiate a study of 1,000 pairs of gay brothers and their families. This study will try to clarify the role of previously studied genetic regions (such as Xq28) as well as attempt to identify other possible regions that influence male sexual orientation. This research may clarify whether a specific genetic region influences the development of sexual orientation in males. One of the advantages of this study is its much larger sample size, which will provide a better chance of finding evidence for genes contributing to sexual orientation. Because of the large number of subjects, we will have more statistical power than previous studies. The relatively low number of participants in other studies has left open the question of whether there is such a gene at Xq28, among other issues.

Of course, finding genes linked to sexual orientation is only part of the story. It will also be important to figure out how genes actually influence sexual orientation. In other words, how do genes actually contribute to sexual orientation? For example, one psychologist has suggested that genes may affect temperament, and that a certain temperament can – in turn – influence the sex perceived as erotically interesting and attractive [24]. Even if this is true, there are many steps to be filled in to explain how genes influence sexual orientation.

The exact role of genes in sexual orientation is unknown at this point, and much more investigation will be required to clarify how influential they actually are in sexual development.

     
For further information, consult the sources below in the references section, which include a sampling of the relevant research papers and books. Please also use the links listed below for information posted on the internet.
     
III. ETHICAL ASPECTS OF SEXUAL ORIENTATION RESEARCH
     
  A. Why do researchers study the development of homosexuality?
     
   

Researchers are interested in all aspects of human development, and sexual orientation is no exception. Sexuality is a key element in human life and is of substantial interest to researchers and other people as well.

One goal of sexual research is to answer the question of how people come to have the sexual interests they have [25]. The study of homosexuality is one part of this larger scientific project.

Not all this research may have direct practical benefits or effects. In other words, sometimes researchers study a topic to produce new information rather than new products or technologies. This is true of ‘basic research’ in general, and it may be true of the study of homosexuality in particular. What is important in basic research such as this is that scientists add to existing knowledge about how human sexual development occurs.

     
  B. Is the study of male homosexuality different from the study of female homosexuality?
     
   

In one sense, there is no difference in the study of male and female homosexuality. The goal of research in both cases is to describe how people come to have the sexual interests they have and why they behave the way they do.

Historically, researchers have focused more on male homosexuality than on female homosexuality. This may have been because it was easier to identify and classify male homosexuality than female homosexuality or because researchers thought it was more important to explain male homosexuality than female homosexuality [26]. Contemporary researchers do not ignore female sexual orientation, however (e.g., see [2, 3]). They recognize that the development of sexual orientation in females is a valid scientific question.

Some commentators have suggested that sexual orientation is more fluid in females than in males. A complete explanation of sexual orientation will have to show whether this is true and if there are, in fact, differences in the development of sexual orientation in males compared to females. Because of likelihoods such as these, we have elected to separately study male and female sexual orientation, beginning with the former.

     
  C. Why is the study of homosexuality controversial?
     
   

Some people believe that the biological study of homosexuality will increase discrimination and prejudice against homosexual men and women. Also, some researchers do not believe this is an important area of study. They think that the study of diseases, for example, is far more important than the study of sexual behavior.

Scientists who study human sexuality do not accept these views. Researchers studying homosexuality believe that research has already done a great deal to dispel myths about homosexuality. Some researchers believe that factual information about homosexuality can help prevent distorted and hostile views [26].

Sex researchers agree that the study of diseases is important. They also believe, however, that it is important to study human psychological development. Because sexuality is an essential part of human life – for individuals and society – they believe it is important to devote some time and resources to human sexual development, homosexuality and sexual orientation in general being part of that field.

     
  D. Do scientists study homosexuality in order to find a ‘cure’ or ‘treatment’?
     
   

Most researchers study homosexuality in order to understand how people come to have the sexual interests they have. In other words, researchers are simply trying to explain why some people have sexual interest in males, in females, in specific sexual practices, and so on. The study of sexual orientation is one part of the scientific study of human sexual development. Therefore, most researchers do not study homosexuality in order to find ‘cures’ or ‘treatments,’ and that is certainly not our motivation.

Some researchers do believe, however, that homosexuality is a mental disorder or dysfunctional psychological adaptation. Some of these researchers would like to find a method to prevent homosexuality or to eliminate it. Most of the world’s leading professional organizations in psychiatry and psychology do not accept this view as sound, and neither do we.

It is unlikely that research will identify any simple intervention that could alter any person’s sexual orientation. Many methods have been tried to date, but there is little evidence that the sexual orientation of adults is open to fundamental change. Sexual orientation in adults is deeply entrenched, no matter how it develops.

Some people seem to think genetic studies of homosexuality may offer more chance for sexual orientation therapies. This is highly unlikely. At the present time, physicians have no way to alter a person’s genetic endowment in order to change any trait having a genetic contribution. While there is considerable research in genetics in general, genetic treatments for sexual orientation are not in the foreseeable future and unlikely to be possible. It bears repeating that interventions like these are not the goals of this research project.

     
  E. Will the study of homosexuality lead people to believe that it is an illness or disorder?
     
   

Some studies have specifically showed that homosexual men do not differ from heterosexual men with regard to key psychological traits [27, 28]. Studies such as these actually led people away from the view that homosexuality is an illness or disorder.

Other studies of homosexuality have not increased the perception that homosexuality is a mental illness or disorder. In fact, some studies may have reduced this perception by showing, for example, that a large number of people engage in homosexual behavior [29, 30, 31].

Of course, it is impossible to predict exactly how the public will interpret and use scientific research. Still, the scientific study of a trait does not mean that the trait is an illness or disorder, and that applies to homosexuality as well.

     
  F. Will future research develop a ‘test’ that makes it possible to discover someone’s sexual orientation?
     
   

There is already a ‘test’ for sexual orientation: researchers (or anyone) can ask people what sexual fantasies and interests they have and how they behave sexually. They can also ask people how they label themselves: as homosexual, bisexual, heterosexual, or otherwise.

Some commentators are worried that researchers will find another kind of test, a biological test that would disclose whether or not someone is homosexual. It is unlikely that there could be a definitive biological test for sexual orientation. For one thing, no studies of homosexual men and women have ever shown that they have biological traits that are entirely distinct from everyone else. Homosexual men and women share traits with everyone else.

If scientists do discover that there is a genetic region linked to sexual orientation in men, they will have to conduct further studies to determine exactly what the genes in this region do. The genes might be associated with some other trait shared by the gay men in the study.

Furthermore, even if researchers do find a genetic region strongly associated with homosexuality, it is highly unlikely that the genes in this region will prove someone’s sexual interests one way or the other. While identical (monozygotic) homosexual twins share all of the same genetic variants, their sexual orientation is often different; one twin might be homosexual and the other might be heterosexual. Sexual interests are complex and influenced by a variety of factors. Anyone can have sexual experiences with a male or a female no matter what genes they carry. It is highly unlikely that sexual orientation will be definitively linked to the presence or absence of a single, identifiable gene variant that can be disclosed through a test, or even a panel of such putative tests.

In short, it is highly unlikely that any biological (including genetic) ‘test’ for sexual orientation will ever be able to replace the accuracy of simply asking people directly about their sexual interests and behavior. It is certainly not our goal to develop such a test.

     
  G. Will research give parents the ability to control the sexual orientation of their children in any way?
     
   

Children with homosexual orientations appear in all kinds of families, regardless of social status, economics, geography, race, ethnicity, religion, or political beliefs.

Some parents do not want to have gay and lesbian children because they disapprove of homosexuality. Some do not want gay and lesbian children in order to spare the children any difficulties growing up in societies that discriminate against gays and lesbians.

Some researchers believe that therapy with children who behave as members of the opposite gender can reduce the likelihood that they will become homosexual. These results are far from conclusive, however. It is also true that many children who become homosexual do not appear any different from their boyhood peers. We are studying both sexual orientation and gender related behaviors as a way of exploring this issue in more detail.

There are no known means that give parents control over the sexual orientation of their children. Genetic research is unlikely to change this situation and that is not our goal either.

     
  H. Will the biological study of homosexuality lead to fewer homosexual people in the world?
     
   

Some commentators fear that hostility to homosexuality might lead people to use genetic tools to produce ‘treatments’ for homosexual men and women [32]. They also worry about the use of sexual orientation tests during pregnancy, in order to avoid pregnancies that might produce a homosexual child [32]. If there were therapies and tests of this kind, would they lead to fewer homosexual people overall?

As a matter of well-established medical ethics and law, adults have the right to decline any and all unwanted therapies and tests. Most homosexual men and women do not want to alter their sexual orientation. As a result it is unlikely that a therapy – if it existed – would significantly alter the total number of homosexual men and women in the world.

If a prenatal test existed (see discussion above regarding this highly unlikely possibility), some prospective parents might use it, but its use would be in some ways limited. First of all, genetic testing of fetuses is complex, and it would be available only in developed countries. Most children in the world are born without any genetic tests, and there is no reason to think that this situation will change simply because researchers find some biological aspect to sexual orientation. It is also true that if there were some way to identify the likely sexual orientation of a child during pregnancy, some people might use that information to try and have homosexual children. Testing might not be used only to avoid having homosexual offspring.

It should be repeated that there is no biological therapy for sexual orientation and no prenatal test that can disclose a child’s likely sexual orientation, situations unlikely to change. These concerns are matters of speculation.

     
IV. LEGAL ASPECTS OF SEXUAL ORIENTATION RESEARCH
     
  A. What is the legal status of homosexuality in the United States?
     
   

Because of a recent decision by the Supreme Court, the law can no longer punish private consensual homosexual behavior involving adults. This is a significant change in United States history. For most of U.S. history, homosexual behavior has been illegal. Most states adopted laws that made ‘sodomy’ criminal, alongside various other sexual practices. These laws focused on behavior, and punishments have sometimes been severe. Homosexual orientation or desires have never been illegal by themselves.

Homosexual orientation or desires have had legal consequences. For example, in the past, the United States has excluded people from immigration and naturalization on the basis of homosexual orientation. Even so, enforcement in those areas has been uneven, as it has been in states with laws against men having sex with men and women having sex with women. In general, the application of laws against homosexuality has been almost random. Even when most jurisdictions had laws against homosexuality, most people were not prosecuted for homosexual behavior. Nevertheless, in 1986 the United States Supreme Court upheld the right of states to make homosexuality criminal, in Bowers v. Hardwick.

In 2003, the Supreme Court reversed itself and said that Bowers had been decided incorrectly. In Lawrence v. Texas, the Supreme Court held that states may not criminalize the sexual relations of men or women so long as those relations are between adults and in private. State law may still prohibit sex between males and sex between females that involves adults having sex with minors or the exchange of money.

Some jurisdictions protect homosexual men and women against discrimination in housing and employment, but other jurisdictions do not. In some places it is perfectly legal to fire men and women from their jobs because of their homosexual orientation. Federal law also excludes certain men and women from service in the United States military for homosexuality if their homosexuality becomes public for any reason.

At the present time, there is a broad social debate about same-sex marriages in the United States. Some states now offer either ‘civil unions’ or even marriage to people of the same sex. By contrast, many other states have laws that expressly forbid the recognition of such unions or marriage.

     
  B. Will research influence the legal status of homosexuality?
     
   

At the present time, states may not pass laws against the private, consensual sexual relations of adults that do not involve money-for-sex. The biological study of homosexuality is unlikely to influence this legal conclusion in any way.

There might be indirect effects of sexual orientation research on the law. Some people seem more tolerant of homosexuality if they believe it is involuntary, something beyond a person’s ability to choose. Biological study might reinforce this view. Changing social opinion about the origins of homosexuality might lead to the adoption of more laws that specifically protect homosexual men and women from discrimination, but this is not certain.

     
  C. Will the biological study of homosexuality lead to new laws?
     
   

Some commentators worry that finding biological and/or genetic aspects to sexual orientation will open the door to discriminatory testing. If there is biological test for sexual orientation (see discussion above), some people might want to use it, for example, to avoid hiring homosexuals or renting homes to them, and so on.

Ordinarily, testing cannot occur without the prior knowledge and consent of the people being tested. If lawmakers found that people were being tested without their consent or that tests results were being used prejudicially, they might consider the adoption of specific laws against this, but this is not certain.

     
REFERENCES
     
 

Bailey JM, Benishay DS (1993a): Familial aggregation of female sexual orientation. American Journal of Psychiatry 150:272-277. PMID: 8422079

Bailey JM, Dunne MP, Martin NG (2000): Genetic and environmental influences on sexual orientation and its correlates in an Australian twin sample. Journal of Personality and Social Psychology 78:524-536. PMID: 10743878

Bailey JM, Pillard RC (1991): A genetic study of male sexual orientation. Archives of General Psychiatry 48:1089-1096. PMID: 1845227

Bailey JM, Pillard RC, Neale MC, Agyei Y (1993b): Heritable factors influence sexual orientation in women. Archives of General Psychiatry 50:217-223. PMID: 8439243

Bailey JM, Zucker KJ (1995): Childhood sex-typed behavior and sexual orientation: A conceptual analysis and quantitative review. Developmental Psychology 31:43-55. Available on PsycINFO

Bayer R (1987): Homosexuality and American Psychiatry: The politics of diagnosis, Second ed. Princeton: Princeton University Press. ISBN: 0691028370

Bell AP, Weinberg MS (1978): Homosexualities: A study of diversity among men and women. New York: Simon and Schuster. ISBN: 0671251503

Bem DJ (1996): Exotic becomes erotic: A developmental theory of sexual orientation. Psychological Review 103:320-335. Available on PsycINFO

Ellis H (1897-1928): Studies in the Psychology of Sex, 7 volumes. ISBN: 0394441834

Freud S (1953 (originally published, 1905)): Three essays on the theory of sexuality, Vol 7. London: Hogarth Press. ISBN: 0465086071

Hall JA, Kimura D (1994): Dermatoglyphic asymmetry and sexual orientation in men. Behavioral Neuroscience 108:1203-1206. PMID: 7893413

Halperin DM (1990): One hundred years of homosexuality and other essays on Greek love. New York: Routledge. ISBN: 0415900972

Hamer DH, Hu S, Magnuson VL, Hu N, Pattatucci AM (1993): A linkage between DNA markers on the X chromosome and male sexual orientation. Science 261:321-327. PMID: 8332896

Hooker E (1957): The adjustment of the male overt homosexual. Journal of Projective Techniques 21:18-31. PMID: 13417147

Hooker E (1958): Male homosexuality in the Rorschach. Journal of Projective Techniques 22:33-54. PMID: 13514724

Hu S, Pattatucci AM, Patterson C, Li L, Fulker DW, Cherny SS, et al (1995): Linkage between sexual orientation and chromosome Xq28 in males but not in females. Nature Genetics 11:248-256. PMID: 7581447

Kallmann FJ (1952): Twin and sibship study of overt male homosexuality. American Journal of Human Genetics 4:136-146. PMID: 14943713

Kinsey AC, Pomeroy WB, Martin CE (1948): Sexual behavior in the human male. Philadelphia: W. B. Saunders Company. ISBN: 0253334128

Kinsey AC, Pomeroy WB, Martin CE, Gebhard PH (1953): Sexual behavior in the human female. Philadelphia: W. B. Saunders Company. ISBN: 025333411X

Laumann EO, Gagnon JH, Michael RT, Michaels S (1994): The social organization of sexuality: sexual practices in the United States. Chicago: The University of Chicago Press. ISBN: 0226469573

LeVay S (1991): A difference in hypothalamic structure between heterosexual and homosexual men. Science 253:1034-1037. PMID: 1887219

Lippa RA (2003): Are 2D:4D finger-length ratios related to sexual orientation? Yes for men, no for women. Journal of Personality and Social Psychology 85:179-188. PMID: 12872893

McFadden D, Pasanen EG (1998): Comparison of the auditory systems of heterosexuals and homosexuals: click-evoked otoacoustic emissions. Proceedings of the National Academy of Sciences U S A 95:2709-2713. PMID: 9482952

Money J (1988): Gay, straight, and in-between: the sexology of erotic orientation. New York: Oxford University Press. ISBN: 0195054075

Murphy TF (1997): Gay science: the ethics of sexual orientation research. New York: Columbia University Press. ISBN: 0231108486

Mustanski BS, DuPree MG, Nievergelt CM, Bocklandt S, Schork NJ, Hamer DH (2005): A genome-wide of male sexual orientation. Human Genetics [Epub ahead of print]. PMID: 15645181

Rahman Q, Kumari V, Wilson GD (2003): Sexual orientation-related differences in prepulse inhibition of the human startle response. Behavioral Neuroscience 117:1096-1102. PMID: 14570558

Rice G, Anderson C, Risch N, Ebers G (1999): Male homosexuality: absence of linkage to microsatellite markers at Xq28. Science 284:665-667. PMID: 10213693

Ruse M (1988): Homosexuality: a philosophical inquiry. Oxford: Basil Blackwell. ISBN: 063115275X

Stein, E (1999): Mismeasure of Desire: The Science, Theory, and Ethics of Sexual Orientation (New York: Oxford University Press). ISBN: 0195099958

von Krafft-Ebing R (1998 (originally published, 1880)): Psychopathia Sexualis. New York: Arcade Publishing. ISBN: 1559704268

Wilson EO (1978): On Human Nature. Cambridge: Harvard University Press. ISBN: 0674634411

     
FURTHER READING
     
  For a discussion of the reasons for studying sexual orientation, see: Murphy TF (2004): Genetic Science and Discrimination. Chronicle of Higher Education, June 4, 2004, 50(39):B17.
     
 

For a wide-ranging list of academic and news media articles dealing with biological aspects of homosexuality, see the relevant portion of the GLBTQ Info-Pages (GLBTQ stands for Gay, Lesbian, Bisexual, Transgender & Queer)

     
  For an ongoing on-line debate on a closely related, but more general topic, see the relevant portion of ProCon.org : Nature v. Nurture -- Is sexual orientation determined at birth?
     
     
COMMUNITY ADVISORY BOARD
     
 

Patrick K. Finnessy, Ph.D., is the Director of the Office of Gay, Lesbian, Bisexual, and Transgender Concerns at the University of Illinois at Chicago. His doctoral degree focus was on gender and women’s studies. His research work focuses on education and the correlation between teacher identity and sexual/gender identity as it pertains to sexual minorities. While earning his master's degree at the University of Illinois at Urbana-Champaign, he created and published a curriculum guide for the anthology Growing up Gay, Growing up Lesbian. He has presented workshops at local, state, and national conferences to counselors, social workers, teachers, professors, and administrators. Prior to his work at the university level, Mr. Finnessy served as a Dean of Students and an English teacher at a large high school in the Chicago suburbs.

     
  Timothy F. Murphy, Ph.D., is Professor of Philosophy in the Biomedical Sciences at the University of Illinois College of Medicine at Chicago. He holds a doctorate in philosophy from Boston College and has taught in the philosophy department at Boston University. He is the author or editor of eight books, including Justice and the Human Genome Project (University of California Press, 1994) and Gay Science: The Ethics of Sexual Orientation Research (Columbia University Press, 1997). His most recent book is Case Studies in Biomedical Research Ethics, published in April by the MIT Press. He is the author of many peer-reviewed articles in such journals as the Journal of Medical Ethics, the Cambridge Quarterly of Healthcare Ethics, Bioethics, the Hastings Center Report, and the Journal of Medicine and Philosophy. He has held grants from the U.S. Department of Defense and the National Institutes of Health, all dealing with ethical, legal, and social implications of genetic research. He is a member of the ethics committee of the American College of Surgeons Oncology Group. In the 2002-2003 academic year, he was a Visiting Scholar at the Institute for Ethics of the American Medical Association in Chicago.
     
  Patricia O’Brien, Ph.D., M.S.W., is an Associate Professor at the University of Illinois at Chicago, Jane Addams College of Social Work. In that role she teaches practice methods, group work, and practice with women. She had post-graduate training at the Inter-university Consortium for Political and Social Research Workshop on Quantitative Analysis of Crime and Criminal Justice. Her practice background is in working with battered women and their children. She has received several awards from the Council on Social Work Education. Her research has been funded by the Lutheran Social Services of Illinois, the National Institute of Drug Abuse, and the U.S. Department of Justice/National Institute of Justice, and the Illinois Department of Human Services. She has written widely on the topic of family relationships, women’s reintegration into families and employment after release from prison. She is the author of Making It in the ‘Free World’: Women in Transition from Prison, and she has lectured widely in both academic and corrections environments. She has served on the Board of Directors of the National Runaway Switchboard and the Editorial Board of the journal, Families in Society.
     
  Kittiwut (Jod) Taywaditep, Ph.D., is a licensed clinical psychologist, holding a doctorate in clinical psychology from the University of Illinois at Chicago. His graduate training focused on prevention of health-risk behavior and involved a series of Centers for Disease Control-funded studies on HIV among at-risk men. His training also involved work at Howard Brown Health Center in Chicago as well as clinical service at the HIV Primary Care Unit at Cook County Hospital in Chicago. Currently, as a staff psychologist at the Counseling Center at the University of Illinois at Chicago, his work includes providing psychotherapy and the supervision of doctoral trainees and paraprofessionals. He is also the coordinator of the InTouch Crisis Hotline, a crisis hotline staffed by undergraduate volunteers that has provided crisis counseling to residents of the Chicagoland area since 1975. He teaches a training course on crisis intervention and supervises paraprofessional volunteers at the hotline. His research interests include gender and human sexuality, HIV/AIDS, prejudices, men and masculinities, clinical work with GLBT clients and individuals of Asian-Pacific descents, and multicultural issues in psychotherapy.
     
RESOURCES FOR THE LGBT COMMUNITY (not connected with our study)
     
 

GLMA: The Gay and Lesbian Medical Association is a non-profit organization committed to ensuring equality in health care for lesbian, gay, bisexual and transgender people and healthcare professionals. See http://www.glma.org/

Several groups and non-profit organizations work to achieve the civil rights of lesbians, gay men, bisexuals, transgender people and those with HIV, through impact litigation, education, and public policy work. See this directory for links to such resources.

Lambda: Lambda is a non-profit gay / lesbian / bisexual / transgender advocacy agency dedicated to reducing homophobia, inequality, hate crimes, and discrimination by encouraging self-acceptance, cooperation, and non-violence. See http://www.lambda.org/

Organizations, and of course individual college and university student LGBT (Lesbian Gay Bisexual and Transgender) groups, work to offer the resources and services important in college, university, and other levels of education. See this directory for links to such resources in the US.

PFLAG: Parents, Family, and Friends of Lesbians and Gays is a non-profit organization focused on the health and well-being of lesbian, gay, and transgendered people. See http://www.pflag.org/

Note: We have also clarified the heading of this section.