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This submission arises out of nearly a decade of study of sexual and gender issues. The author is a member of St John's Anglican Church, Trentham, co-author of a 190 page book submitted to the Justice and Law Reform Select Committee on the Human Rights Amendment Bill 1992 (ISBN 0-473-01949-3) co-author of a book at third draft stage ("My Genes Made Me Do It") dealing with behavioural genetics, and has so far 4 academic papers on the subject (including two in press and a letter to Nature). Besides the strictly academic papers he has a published letter to Time magazine. He has given numerous talks to churches, Bible Colleges and counselling groups, both here and in Australia. His initial academic training was in biochemistry, but during the last 25 years as a practising scientist has considerably diversified. Besides the above he has a total of about 85 published papers and numerous reports. He helped with the research for his wife's book (Whitehead, 1993).

In the course of reading all the submissions to the 1993 select committee on the 1992 Bill, it became clear that when church groups of whatever opinion had made submissions they were distressingly ill-informed about the scientific issues involved. This general ignorance as found in the United Kingdom was even made the subject of a 1995 editorial in the journal New Scientist

"The church should not condemn affairs as sinful and wrong," the Bishop of Edinburgh said last week, sparking off a furore.

"In search of an ally, the Bishop appears to have added adultery to the long list of weaknesses that people now feel entitled to blame on their genes. Unfortunately those arguments rely on a popular form of false reductionism." (Anon. 1995)

By this the editor meant it is too simple -- in fact simply wrong -- to say "My genes made me do it". Most media articles suggest our genes force us to smoke, become bulimic, give us infallibly a high IQ, etc. They don't, and this submission expresses why not. It is based on primary sources (articles and reviews in professional journals) and in a few cases more accessible references consistent with that literature. The document represents mainstream, consensus views in the scientific community but in a very condensed way, and much more reference material is available if the commission wishes it. The views given here, as well as being science-based, have theological and pastoral implications which are pursued in Part II.

No genetic dictation of behaviour. The most important point, which is held strongly by all working scientists in the field, is that Biology or Genetics never dictates human behaviour; at the very most it may influence it to some degree, but that degree is much less than the environmental influence.

Humans do have some behaviours which are instincts (hence possibly dictating behaviour), including breathing, self-preservation, eating, drinking and sleeping. However it is clear that the last four can be modified in major ways. The Church has long advocated "laying down one's life for one's friends", fasting, and watching, with prayer. Even these basic instincts can be trained and modified, and all other less basic behaviours such as those associated with gender and reproduction can be even more easily changed.

Those scientists who publish material which argues there is some genetic contribution to a sexual condition are very careful to say that these influences are far from determinative; this is because no other view can be defended in the scientific community without ignoring the facts. This consensus has been expressed in various ways, for example

"In writing the biography of great men and women, printing the DNA sequence of their genome would not be a good place to start."(Cook-Degan, 1993)

"We are not hostage to our ancestors" (Lykken, 1982)

"Anatomy is not destiny" (Blum, 1992)

"If a certain form of psychopathology should be caused primarily by genes it might be mistakenly assumed that psychotherapy and other environmental intervention would be useless. This pessimistic view is simply wrong. Genes do not determine one's destiny." (Plomin, De Fries, & McClean, 1980)

"...human learning and culture override any relevance biology may have for the explanation of human behavior....Biological determinism is what people often think of first when they hear of a biological theory. That's a shame - because it's been years if not decades since "biological" has meant "biologically deterministic"...Men are genetically predisposed to grow hair on their faces, but most American men override that predisposition every morning by performing an unnatural act in front of a mirror." (Weinrich, 1990)

Environmental effects Environmental factors although predominant, do not completely determine human behaviour either. Virtually all scientists agree that the truth is "interactionist" -- i.e. the biological structure and the environment interact, and the behaviour results from both (Heath, Jardine, & Martin, 1989). There may even be some genetic influence on the selection of environments by individuals (Plomin & Bergeman, 1991) and other more complex interactions (Truett et al., 1994). There is also universal agreement that lower animals are far more subject to genetic influence, and have less choice. As one ascends to humans, the importance of the environment and of choice becomes very strong (Nadler, 1990):

"...the available literature suggests that humans have not escaped completely from the endocrinological control of sexual behaviour and that humans are similar in certain ways to the other mammals. On the other hand it is also obvious that social learning plays an extremely important role in human sexual behavior." (Segraves, 1988; see also Whalen, Geary, & Johnson, 1990).

"...Animal studies of the sexual differentiation process have not provided useful insight into the biological basis of human sexual preference." (Whalen, Geary, & Johnson, 1990)

In other words animals are at the most bisexual -- there is virtually no same sex exclusivity and what does exist does not help explain human homosexuality.

Environmental influences are able to be changed much more easily than the biological, and hence can be made to overwhelm them. It is possible to change a person's behaviour by psychotherapy - but this is not presently possible through gene therapy. Environmental change can effect behaviour, and even biological conditions. For example in Wilson's disease, there is a genetic defect which causes accumulation of copper in the body, and unpleasant medical side-effects. This is an extreme example, because if the gene defect is present, the condition is determined and will inevitably occur, but it can be completely overcome by environmental intervention; the use of a drug called penicillamine which removes the copper (Denny-Brown, 1963).

An even more interesting example is porphyria, familiar from the recent film The Madness of King George. It has been known for several decades that his condition was due to a genetic defect that made large quantities of biochemicals called porphyrin derivatives circulate in the blood. These caused periodic mental derangement. In the film, it appeared that the psychological treatment of Dr Willis involving restraint and calming, was helpful. This was medically correct; the patient is more prone to porphyria under conditions of severe excitement, and if specially calmed may pass into remission. Today, giving a patient tranquillisers (which only change his mental state, not the incorrect metabolism occurring) is usually sufficient to interrupt the vicious cycle of attacks (Watson, 1963). This shows vividly how even psychological intervention may correct the effects of a genetic and physical disease.

These general conclusions tend to get particularly questioned by the layperson in the realm of the sexual, because gender behaviours or sexual orientation seem so unalterable and this may be from personal experience. Unfortunately many people reinforce this belief by reading the conclusion of a piece of scientific work on sexual behaviour, finding a mention of "genetic" and concluding, always contrary to the detail of the original text, that the behaviour is dictated by the genes.

Incidence of various sexual-associated conditions among Christians Sex is important to everyone, including Christians, but gets relatively little useful attention pastorally. Some modern surveys of sexual life and gender issues contain incidence data specifically on Christians.

The following data are assembled from Hart (1994). It is not a true random sample, and represents only about 600 men. They are predominantly "conservative Christians" from the USA. The data probably present only an approximation of the incidence of the various behaviours in the NZ Church communities.

The following suggest the significant frequency of sexual acts, and probably their importance to those who do them. For teenagers of age 16, 23% reported zero masturbation per month, 48% 5-10 times per month, 13% 15-20. Significantly the results for married men were almost identical. About 20% of married men regarded their masturbation as either an addiction or a habit but 97% of those who masturbated did not feel guilty about it. As regards thoughts rather than action, 61% thought about sex daily, 18% weekly and 16% thought about it hourly. There was only a slight decrease with age. Those who admitted to achieving stimulation through fantasy with a person not their spouse numbered 57% . Although 45% found their current sexual experience good and 30% rated it as excellent, 20% rated it as fair only. The conclusion from the above data is that the subject is very important to most men, but does not receive a proportionate share of attention in the church.

Ninety four percent had been exposed to pornography. Specifically 91% of those raised in Christian homes reported having been exposed to pornography at least once (compared with 98% of those from non-Christian homes). Eighty-four percent experienced this as harmful, 3% neutral, 3% useful. Seventy percent found it addicting to some extent, and 71% found it destructive. Eighty percent thought it was degrading towards women. Masturbation to pornography involved 15.5% of lay married men and 6.8% of married clergy. If these data are reliable they suggest that about 10% of men are masturbating to pornography and finding it somewhat addicting.

One percent reported attraction to the same sex and 0.27% exclusively so (these results if reliable are rather low compared with surveys given later describing incidence in the general population). About 1% rather remarkably, volunteered the information they were once

"...homosexual in behavior but now ..satisfied and adjusted heterosexuals".

This is also known from reliable surveys in the general population, but the corresponding percentage there is about 2%. In both cases this appears to refer to spontaneous change, perhaps from adolescent experimentation. The following additional data (Corporate research department of Christianity Today Incorporated, 1987) are extracted from a survey by Christianity Today, and therefore mainly represent the evangelical community, but should be noted because it seems likely even if the true incidences are rather different they still represent the importance of sexual matters to the community of faith, and the fact that there is little help available.

Most pastors said they did not dare seek counselling -- they were afraid word would leak out. This again points to a need for counselling availability for this important facet of men's lives. Counsellors observe that women are considerably more prone to seek help in this and other areas.

General population sexual behaviours One little known fact is that both youthful promiscuity and celibacy are becoming more popular in our society. The data are taken from Laumann, Gagnon, Michael, & Michaels, (1994) and show two extremes in sexual behaviour in the general population.

There is now a tendency to greater celibacy before age 20 than in older generations. The celibacy figures are probably partly due to the influence of the AIDS epidemic but show it is not inevitable that young people will be promiscuous, and the fraction of those who are celibate is considerable. There are still strong pressures on young people to have sex while young and although the incidence for men has been static for some years, that for women is still increasing.

The same source suggests that since age 18, for men the maximum mean length of relationship was 1.3 years for heterosexuals and 0.5 years for homosexuals. For women it was 4 years for heterosexuals and 1 year for lesbians. This clearly includes a few people with very many transitory relationships which lower the average, because those who were currently married (more than half) averaged about 7 years per relationship.

The survey material is unanimous in declaring that a significant minority of the adult population are simply uninterested in sex at all. In the same survey (Laumann, Gagnon, Michael, & Michaels, 1994) 12.3% of men and 12.7% of women aged 18-59 report no sex partners in the last 12 months. Another survey found 20 and 30% (Trocki, 1992). Leiblum & Rosen, (1988) quote a study in which 17% of women aged 35-39 from a non-patient population had impaired sexual interest and McGonaghy, Buhrich, & Silove, (1994) found 5.6% of adolescents actually class themselves as asexual. In another survey of the general population 3% claimed to be asexual (Cameron, Cameron, & Proctor, 1989). In response to questions in a Kinsey 1970 survey, the men and women who said they saw no prospect of sexual enjoyment with either sex were 8.9% and 11.8% respectively (Klassen, Williams, & Levitt, 1989). Some of this is a reaction to early or more recent sexual abuse, or may simply be a species of burn-out from a stressful or difficult marriage.

Some of the above folk have never been interested in sex; they were not genetically or biologically forced to be heterosexual. They are entirely happy with their state. This shows that heterosexuality is not inevitable, or biologically forced on an individual. Others were interested, and even married, but became uninterested. Their circumstances made them no longer functionally heterosexual. This is evidence of the changeability of sexuality, but also suggests the presence of many who are not happy with their current sexual status, and may need help.

The evidence above is that church folk have about the same percentages of most sexual behaviours as the general population including those traditionally called immoral. This includes homosexuality. There are now a large number of reliable random surveys of the incidence of homosexuality in the population, and since about 1989 it has been clear that the mean incidence of exclusive male homosexuality is about 1% (not 10%), while those bisexual would be about 4% (Bell, Weinberg, & Hammersmith, 1981; Cameron et al., 1985; Fay, Turner, Klassen, & Gagnon, 1989; Rogers & Turner, 1991; Smith, 1991; ACSF investigators, 1992; Johnson, Wadsworth, Wellings, Bradshaw, & Field, 1992; Remafedi, Resnick, Blum, & Harris, 1992; Trocki, 1992; Billy et al. 1993; Laumann, Gagnon, Michael, & Michaels, 1994; the results for Christians above, are identical). The exclusive lesbian incidence is similarly about 0.7% (similarly expected within the church). Figures for the general New Zealand population from a recent survey are 2% bisexual+homosexual, and 2% bisexual+lesbian, but << 0.5% were exclusively homosexual or lesbian (Paul et al. 1995). The percentages are related to the degree of urbanisation, and the above percentages are based on random sampling of the entire population.

A particular type of homosexual minority within the church needs unusual help -- the married active homosexual (often classified as a bisexual). The surveys differ, but of all homosexually active males, about 55 % are married, with a range of 25-80%, and the true figure is likely to be well towards the upper end of the scale (Gebhard, Gagnon, Pomeroy, & Christenson, 1965; Humphreys, 1970; Fay, Turner, Klassen, & Gagnon, 1989; Ross, 1990; Laumann, Gagnon, Michael & Michaels, 1994). In almost all cases their wives have not the slightest idea about their husband's double life. This is indefensible exploitation of women and children; covert, but potentially exposing the wives to the HIV virus, or other STD's. If the behaviour becomes known the effects on the family are devastating, and lead to divorce in most cases (Matteson, 1985). It is likely there is at least one such man in most urban congregations of more than 100 people. A large fraction of these men only become aware of homosexual feelings after marriage (Matteson, 1985); another large fraction are fully aware of their feelings and deliberately enter marriage to gain the advantages of both lifestyles simultaneously (Ross, 1983). It must be emphasised that in no way can a married man or woman acting out homosexually as well, be acting in love towards their spouse and family. A potential, though difficult, solution to this pastoral problem, which appears to be becoming more frequent, is suggested below.

Much of the rest of this document will deal with homosexuality, but this is mainly because it is extremely political, and arguments connected with it have been very widely and effectively spread, often in flat contradiction to the scientific findings which are that for both homosexuality and heterosexuality, genes or their biological expression do not determine the behaviour, or identity.

One red herring should possibly be disposed of at this stage. An examination of the DSM-IV diagnostic manual of the American Psychiatric Association (APA) shows that homosexuality is no longer classed as a disorder. However the same manual does not consider pederasty, fetishism or sadomasochism as disorders either, which means no judgement as to normality or acceptability is implied. Additionally, according to Richard Isay the chairman of the APA Gay, Lesbian and Bisexual Issues Subcommittee (Letter to the New York Times 25 April, 1993), most psychiatrists still believe that homosexuality is disordered and that sexual orientation change is possible under therapy. Many psychiatrists disagree so strongly with the official stance of their association that they have formed the North American Research into Therapy for Homosexuality, group (NARTH). The original decision to declare homosexuality not a disorder, taken by the APA in 1973 was taken under extraordinary duress (physical threats, intimidation, forging of credentials etc.) and the vote was shown to be representative of the views of not more than 25% of the members (Magnuson, 1990; Rekers, 1982). The APA stance is frankly political and has really no bearing on the scientific question of origins or changeability.

Genetic association with reproductive behaviour

Any sexual behaviour which is oriented towards reproduction is probably connected with genes which are passed on to descendants. Such genes tend to be concentrated, and selected for, in a population. In contrast behaviours which tend to prevent reproduction will tend not to be passed on. They will not be concentrated in the population, and should require a considerably larger element of learning. Since the degree of learning for heterosexuality is so large, there should be an even greater learning component for behaviours such as celibacy, exclusive homosexuality, suicidal impulses or other things which tend towards blocking reproduction.

In general terms, since homosexuality tends to lead away from reproduction, it should be very strongly selected against, and it is very hard for geneticists to see how such genes, if they existed would be able to survive in the population. The rate of production of such genes (presumably by mutation) would have to be about 1% per generation, if it was to replace the rate of loss of any genes for exclusive homosexuality. This is about a thousand times higher than any other known individual mutation rate in the human population (Cooper & Krawczak, 1993). Various authors have reviewed means by which such genes might survive in the population (Weinrich, 1990), but it is fair to say geneticists regard them dubiously. For example, some have suggested that if childless people spent a lot of time helping their nearest relatives bring up their children, their genes (some of which would be the same as their relatives') would tend to be preserved in those children. But today gay or lesbians prefer to live with someone else similar rather than with their nearest relatives. This basic genetic difficulty is so severe that geneticists therefore prefer to think that learning processes must overwhelmingly predominate.

All known medical conditions caused by genetic defects in humans have incidences which sum to about 1% (Cooper & Krawczak, 1993). It is highly unlikely that homosexuality with an individual incidence of about 4% (including 1% exclusive homosexual) can fall in the category of being genetically caused.

In lower animals, behaviours are connected with large numbers of genes (Plomin, 1990), and that would be expected for humans too if the behaviour is really genetically linked. In animals, the result of this is slow change of behaviours in animals during selective breeding, with behaviour characteristics very apparent for three or four generations at least, instead of vanishing in a single generation as can happen for a physical or medical condition if only one gene is involved. One would expect homosexuality to be associated with many genes like other behaviours, and hence to disappear rather slowly in a family tree. But homosexuality in families though associated with family structure (Pillard, 1990), has quite a spotty occurrence and may appear and disappear in a single generation. This suggests it may well not be genetic at all, but shows at the same time there is evidence for family influence.

Evidence from culture and anthropology

Evidence from sexology literature

Subsequent work found large amounts of spontaneous change occurring in populations (West, 1977; Ross, 1983; Dixon, 1985; Richardson, 1987; Nichols, 1988; Cass, 1990) both toward and away from homosexuality. One common clinical pattern is to see women who become lesbian in middle age, often after marriage, family, and a divorce, with no prior lesbian feelings or fantasy at all (Cass, 1990). This fits one prominent version of lesbian ideology which insists that no-one is born with a particular sexual orientation, but that it is constructed, and should be deliberately constructed, by the individual woman - preferably as a lesbian orientation for political solidarity (Kitzuger & Wilkinson, 1995).

Another example of change is documented in the recent book from the Kinsey Institute concerning bisexuals. Many showed significant shifts in their position on the orientation scale when resurveyed five years later, and a few of the shifts (mainly towards lesbianism) were remarkably large (Weinberg, Williams, & Pryor, 1994).

So much change in sexual preference is observed and well established, that very few sexologists would agree that sexual orientation is fixed and final throughout the lifetime. Some argue for a difference between orientation and identity and that orientation might be changeable whereas identity might be fixed (Reiter, 1989), but the case is speculative and no evidence has been documented. Similarly there is plenty of evidence of change being possible in various non-mainstream heterosexual conditions.

Because this spontaneous change exists and is well documented, it seems clear that neither biology nor genes force a particular sexual orientation on any individual.

Direct evidence for therapeutic change of sexual orientation

"every study ever performed on conversion from homosexual to heterosexual orientation has produced some successes" (West, 1977)

"at least as frequently in homosexual persons as in people afflicted by any other personality disorder." (Cappon, 1965)

In the last 20 years, various amateur therapy groups have formed (Comiskey, 1989; Mesmer, 1992; Coughlan, 1993) which bear a strong resemblance to Alcoholics Anonymous, and help with sexual orientation change (not just to celibacy). The change usually demands as much help as an alcoholic requires, similarly takes a few years, and relies on the help of a specific higher power - God the Father - repair of poor family relationships, making a break with the previous lifestyle, acceptance by same-sex peers, teaching on techniques to break the addictive cycle, and accountability to the group, or a counsellor. The results numerically seem rather similar to those of Alcoholics Anonymous (Whitehead & Whitehead, 1993). Most who stay with the groups for a few years achieve for the first time genuine attraction to the opposite sex, and a very large or complete cessation of attraction to the same sex. Occasionally this may come very simply from strong same-sex non-erotic acceptance. Their overall well-being becomes high (Nicolosi, 1991; Mesmer, 1992). Many eventually marry very happily.

Observation of such groups for a few years makes it undeniable and obvious that real change is possible, though difficult. Rather like alcoholics however, many who have changed want to get on with their new life, and fade into anonymity, being rather ashamed to talk about what they once were. Those few who stand up in public and testify to the change are just a small minority.

The umbrella group Exodus International which has about 150 groups affiliated worldwide has estimated about 2000 individuals have achieved very significant change of sexual orientation (personal communication). Other similar groups exist outside this umbrella. Similar groups exist for those who are caught up in various heterosexual behaviours for which they want help (Schneider & Schneider, 1990), but the numbers internationally appear proportionately far smaller than the groups for homosexuals, which argues a strong imbalance -- the number needing help with heterosexual problems is far larger and there should be more groups for them, but in general homosexuals are far more aware of problems. Perhaps heterosexuals are lazy. All such groups should be specifically encouraged by the Church, particularly since groups for homosexuals, in a form of discrimination, have often been ferociously attacked and harassed even in New Zealand (death threats, phoned obscenity etc.) (Whitehead, & Whitehead, 1993).

A common feature of these groups, and the experience of therapists, is that many features of sexuality, heterosexual or homosexual, are rather compulsive (e.g. Pincu, 1989). This is seen most vividly in the behaviour of those who continue to have unprotected sex, even though knowing themselves HIV+ (this percentage may be as high as 40%, Bartholow et al. 1990, Meyer-Bahlburg et al. 1991).

Change of behaviour, character and desire are possible; they are not fixed, fated, or determined. This is entirely what would be predicted from the previous pages and there are very many books on the subject which contain abundant evidence and numerous testimonies (Payne, 1981a, b, 1985; Comiskey, 1989; Howard, 1991; Davies & Rentzel, 1993; Whitehead, 1993).

There is thus another solution to the problem of the married homosexual, besides acquiescence to the unpleasant alternatives of unfaithfulness or divorce - change of orientation. However those whose behaviour comes to light often cannot see why they should even attempt to change. They seem to think they should be allowed all the benefits of family life while continuing homosexual sex as well. Unless they are strongly motivated, referral to counsellors or support groups usually proves futile, but the church can at least offer that option, and the chance of success is best if there are available the testimonies of those who have made the change.

The church should be made considerably more aware of the impact of another condition which has sexual roots, and is frequently encountered, though until recently it has not gained much prominence. Emotional dependency is a condition in which there is an inordinate affection towards another human. This can occur in parent/child, teacher/pupil, counsellor/counsellee, man/woman but seems especially prone to attack women. It is a demand for emotional exclusivity, and has many addictive elements. It can and does severely disrupt relationships and congregations. Essentially it is another little idolatry, and demands much the same treatment as the above support groups normally give - an examination of the roots and treatment of them (Norwood, 1988; Rentzel, 1990; Whitehead, 1993).

Recent research material on homosexuality.

Brain structure
There are several papers on brain structure which claim to show differences between homosexual men or women and heterosexual men or women and imply the different structures may cause different sexual behaviour or identity (LeVay, 1991; Byne & Parsons, 1993). These are not accepted by the scientific community as very compelling because the methodology is difficult and replication of these studies is notoriously difficult (Breedlove, 1992; Byne & Parsons, 1993). It is also now well known that the structures in the brain change anatomically and enlarge significantly in response to learning (Kandel &Hawkins, 1992), and even the strongest proponents of determinist arguments agree that learning or behaviour could be the origin of brain structure changes, rather than the structure producing the behaviour. E.g. LeVay, the most cited author in this field says

"...the results do not allow to decide if the size of the INAH3 [a structure in the hypothalamus within the brain] in an individual is the cause or consequence of that individual's sexual orientation" (LeVay, 1991).

Gene sequences
There is so far one paper which used a technique called a linkage study to show a correlation between homosexuality and genetic sequences on the X-Chromosome (Hamer, Hu, Magnuson, Hu, & Pattatucci, 1993). About 70% of their homosexual subjects showed variations of the same sequence. The study was criticised by the originator of their statistical methods because the methods were misused, and the significance of the result greatly overstated (Risch, Squires-Wheeler, & Keen, 1993). Such linkage studies are also notorious in the scientific community for lack of repeatability (Horgan, 1993), and even though Hamer has replicated his result, though with even less statistical significance (Holden, 1995, Marshall, 1995) it is still not clear how many non-homosexuals have the genetic region in question. He could not find this structure in lesbians and the correlation is only moderate, even for males. Hamer gives an upper limit of 30% on the fraction of gays who might experience some influence from the genetic structure he found (Hamer & Copeland, 1994). An independent study has found no trace of the linkage, and Hamer in 1995 was under investigation by an ethics committee of the National Institute of Health for alleged selective reporting of results (Marshall, 1995). There is general scientific agreement with the commentary which said

"Hamer's gene, whatever it turns out to be, is neither necessary nor sufficient to determine homosexual orientation (Holmes, 1994)".

" There will never be a test that will say for certain whether a child will be gay. We know that for certain" (Holmes, 1994)

Prenatal hormone exposure
Prenatal hormone studies arise from exposure of developing babies to extreme levels of sex hormones, either natural (enzyme defects), or through anti-miscarriage hormonal treatments (used a few decades ago, but no longer thought good medical procedure). The results may be summed up as showing that there could be a very small effect on later orientation in a few cases but even that is doubtful. Meyer-Bahlburg et al. (1995) found 7 of 117 women subjects exposed to prenatal estrogens were bisexual and none were exclusively lesbian (which although a slightly raised incidence is statistically just compatible with the expected incidence of about 2 in his group - (Laumann et al. 1994). Lish et al. (1992) in the largest and most thorough study so far of women exposed to prenatal diethylstilbestrol found no sexual orientation differences (previous studies had given conflicting results). Congenital adrenal hyperplasia exposes developing girls to abnormal levels of masculine hormones, and subsequent studies have given rather conflicting results. One study (Money et al. 1984) found no exclusive lesbian orientation, but a claimed incidence of 37% bisexuality (attitudes only, not behaviour). However a matched group of diabetic girls with similar age and hospital experience gave the same result (Vines, 1992) showing hospitalisation itself may affect patients' attitudes to themselves and making it unlikely the hormones themselves were responsible.

No effects have been found for boys in any study; excess masculine hormones do not eliminate homosexuality, and excess female hormones do not increase it.

So in summary there is no evidence for effects on male homosexuality, and weak evidence for effects on female homosexuality.

The levels of hormone exposure are very high, but the authors of the various studies are at pains to state that even these extreme levels of exposure do not determine sexual orientation.

"In summary the evidence from prenatal endocrine disorders and from the offspring of hormone-treated pregnancies suggests that hormones may contribute to but do not actually determine, the course of sexual orientation in individuals with an abnormal sex-steroid history during prenatal life" (Gooren, 1990)

"Some degree of prenatal exposure to and utilisation of androgens seems to 'facilitate' but not to fully determine the development of erotic attraction to female individuals". "We also want to emphasise that we do not think that a given biological factor by itself can plausibly be expected to fully determine a complex behaviour such as homosexual orientation." (Meyer-Bahlburg et al., 1995)

Twin studies
Twin studies are based on the fact that identical twins are identical genetically. If one twin is homosexual or lesbian, and if the behaviour/identity is determined genetically, the co-twin should always have the same sexual orientation. To date, the combined results of seven recent studies show that the sexual orientation is the same in only about 50-60% of the cases for the co-twin ( Eckert et al. 1986; Bailey & Pillard, 1991; Buhrich et al., 1991; King & McDonald, 1992; Whitam et al., 1993; Bailey et al, 1993; Holden, 1995) and comparisons with non-identical twins show a large fraction of the concordance is due to causes in the environment. Only a minority of the above results are for lesbians, and they suggest a significantly lower concordance for the co-twin and an even higher influence of the environment. This makes it quite certain for both male and female homosexuality, that the genetic structure is not determinative. As stated by West in connection with twin studies:

" ...they show that the homosexual condition cannot be completely and inevitably predetermined by heredity." (West, 1977)

Change of orientation at puberty
Some studies have been publicised in the media, particularly on individuals from the Dominican Republic, in which it is claimed that changing hormonal status at puberty completely changes (and hence dominates) sexual orientation. There is a genetically caused failure of development of male genitalia before birth in some boys, and although they are brought up as girls, at puberty the male genitalia grow to normal size (Imperato-McGinley, Peterson, Gautier, & Sturla, 1979). Sixty five percent of these "girls" spontaneously changed to live as men (Herdt 1990). However this percentage varies according to culture - in the some West only 10% of those affected chose to change (and found it prolonged and difficult), and in a related defect found among families in the Gaza strip the figure was 28% (R 94sler & Kohn, 1983). The superior social status of men in some of these cultures probably influences choices. But the evidence obviously shows that the biological change itself does not determine sexual orientation and that substantial learning is involved, which is linked with the culture.

Summary
In summary, many lines of evidence suggest a strong learning component in homosexuality and a weak genetic influence, if any. The following groups would choose a genetic influence near zero: anthropologists, cultural historians, developmental psychologists, population geneticists, sexologists, and the majority of therapists.

Endocrinologists would opt for a low figure, twin study experts would say there was some influence, and molecular biologists would say it should not be greater than 30%.

The situation is summed up in two quotations, one from the Kinsey Institute (Rekers, 1982);

"Homosexual practices in the end are chosen behaviour. No biological, social or psychological factor or combination of factors has been found to force a person to choose to engage in homosexual behavior".

".. it seems clear that the final outcome as regards sexual orientation as in most aspects of human personality, depends upon an interaction between environmental circumstances and constitutional predisposition. Usually the two sets of influences reinforce each other, but when they happen to conflict environmental pressures are likely to be the more decisive as determinants of an individual's sexual orientation."

To this I would add that heterosexual conditions which appear enslaving can also be helped by sufficient environmental intervention, such as counselling and support groups.

Possible exploitative aspects of some non-conventional sex

The same source reported that 2.8% of men admitted forcing a woman sexually (this and the following are probably not always equivalent to rape, but are not welcomed or whole-heartedly agreed to by the recipients), and 1.5% of the women admitted coercing in some sense a man to have sex. However 22% of the women reported having to submit to unwelcome sex from a man. This suggests there is a serious question whether all forms of sex even within marriage are justifiable; probably quite a proportion are exploitation.

Previous work summarised elsewhere (Whitehead & Whitehead, 1993) in regards to the spread of the HIV virus shows clearly that the main problem is not lack of knowledge about transmission routes (Chetwynd, 1989; Sonenstein, Pleck, & Ku, 1989; Connell et al., 1990), but failure of control in spite of that knowledge (Stall, Heurtin-Roberts, McKusick, Hoff, & Lang, 1990; Rosser, 1991; ACSF investigators, 1992), and in many cases even if HIV+ (Adib, Joseph, Ostrow, & James, 1991; Meyer-Bahlburg et al., 1991). It has been shown that the best answer to this is small-group therapy (Pincu, 1989; Kelly & St Lawrence, 1990), again equivalent to Alcoholics Anonymous. The Commission would do well to avoid the simplistic insistence that education is the complete answer or even a near-complete answer, and should encourage small support groups.

Summary

Probably there should on average appear over the next few years a few papers a year which point to some new correlation between genes or biology and homosexuality. However it seems very improbable any discovery will prove beyond reasonable doubt that sexual conditions or behaviour of any type are innate and inescapable.

Last modified 7 February 1996