[last updated 13 Sept 2006]
Androgen Insensitivity Syndrome (AIS) is one of a number of biological intersex conditions. Intersex is a variant from the usual embryological development of the reproductive tract, often determined by a known genetic mutation.
So firstly, what is intersex?
The usual pattern of human foetal development results in a 3-part alignment, as follows
1 (sex chromosomes = XY) ---> 2 (gonads = testes) ---> 3 (external genitalia = male)
1 (sex chromosomes = XX) ---> 2 (gonads = ovaries) ---> 3 (external genitalia = female)
... is a type of intersex condition in which the person actually has a male/female mix at the genetic (sex chromosome) level and at the gonadal level. This is extremely rare and very few members of our group are in this situation. The old term for this situation is a hermaphrodite. Note however that a hermaphrodite, in the sense understood by most of society, is a purely mythical creature from ancient literature, one that supposedly has a complete working set of both male and female internal and external organs (such that the individual can, in theory, impregnate itself). This is not humanly possible. Unfortunately medicine took over this literary term in the days before genetics was understood and employed it as a medical term, to refer to these individuals who have both ovarian and testicular tissue internally (an ovo-testis) and who, as a result, can have ambiguous external genitalia.
... is the type of intersex condition in which the sex chromosomes are either XY or XX (i.e. not a mixture) and the gonads are either testes or ovaries (i.e. not a mixture) - as in the majority of the population - but there is a mismatch or distortion in the usual 3-part alignment of these two elements with the external genitalia.
This means that you can, for example, have an XY individual with testes but with an external appearance that is essentially female (i.e. an XY female: either completely female as in Complete AIS, or partly female as in Partial AIS) or an XX individual with ovaries but with some degree of male genital appearance (e.g. a woman with congenital adrenal hyperplasia CAH).
Note that the term 'intersex' refers to the elements of this entire alignment (the sex chromosomes, the gonads and the genitalia), and not just to the appearance of the external genitalia. A patient with the complete form of AIS (CAIS), or with Swyers Syndrome (XY gonadal dysgenesis), will always appear female externally (no ambiguity) but she is still intersexed, because she has XY chromosomes and internal testes (testicular streak gonads in the case of Swyers) that are at odds with her external femaleness.
Before we get into a basic introduction to what AIS is, in medical terms, a brief but important diversion to the subject of bad/confusing terminology and how the media can make things worse.
Intersex is not the same as a transsexual (gender dysphoria) or as a transgender state. Neither term is one that we recognise as belonging in any general discussion of intersex. We are not happy with the recent tendency of some trans groups/people to promote transgender as an umbrella term to encompass, for example, transsexuality, transvestitism and intersex. We object to other organisations/individuals putting us in categories without consulting us, especially categories that imply that interexed people, of necessity, have gender identity issues.
The problems this causes...
We are constantly trying to get away from the idea that intersex is necessarily to do with gender identity, a notion that others (including the press/media) like to impose on us. Moreover, the prefix trans- infers a "moving across" and although a few people with intersex conditions may choose to change their gender role, the vast majority never "go" anywhere in terms of their sex or their gender, but are happy to stay in the status in which they grew up.
People may suffer various problems on finding out their diagnosis.... problems such as confusion, anger at secrecy and paternalism (withholding of diagnostic information), shame, an existential type of identity crisis, low self-esteem, difficulty grasping how this biological phenomenon can come about, grief at being denied fertility and rites of passage (e.g. lack of menstruation), a feeling of freakishness and isolation compared to their peers, a fear that others might see them as 'male', a concern regarding their ability to function in a relationship (e.g. vaginal hypoplasia), the burden of keeping a secret or uncertainty over who to tell and how, a retreat from medical care leading to failure to take HRT with a risk of osteoporosis, etc., etc..... These are the issues that are of major concern to most of our members; and none of these issues necessarily means that their inner sense of being a man or a woman, or intersexed, is compromised.
This trend towards 'muscling in' on intersex issues seems to be a initiative on the part of certain politically-minded people in the 'trans' community, to bring intersex under their banner (for whatever reason - it lends more credibility to their cause?) or even to actively interfere in clinical issues relating to intersex. See Announcements for an account of the problems we had in 2000 with a gender dysphoria/transsexual organisation trying to interfere in protocols for 'gender reinforcement' surgery in intersexed infants with so-called genital ambiguity.
The term 'ambiguous genitalia' refers to one specific component of the intersex state, i.e. the form taken by the external genitalia in a some cases. Sometimes even specialist clinicians use the term 'intersex' wrongly, to mean 'ambiguous genitalia', forgetting that in doing so they exclude the large segment of intersexed patients who have a completely female phenotype (body form) and, usually, no gender or gender identity conflicts at all.
The problems this causes...
This sloppy use of terminology causes us a lot of problems because the media (magazines, newspapers, TV) pick up on this and assume that 'intersex = ambiguous genitalia = gender identity problem', then print/broadcast material that conveys to the general public the idea that gender identity is, of necessity, an issue in intersex... which it absolutely is not.
The vast majority of our members have a secure female gender identity. Yet it has been known for a CAIS group member (with, by definition, no genital ambiguity) to agree the text of an article based on her story (one that concentrates on secrecy, confusion about her diagnosis, isolation etc.) only to find at publication that the editor has slipped in a composite picture (e.g. the left half of a man's photo joined to the right half of a woman's photo) with a caption that says "[Name] is confused about being a man or a woman". .... and just because they have this fixed idea that if you're intersexed then you must have a gender identity problem (and because, of course, this notion sells more magazines/newpapers). See AIS in Articles/Books.
Or else an article will discuss the issues quite sensibly, using the non-emotive term 'androgen insensitivity', but when the group member finally sees it on the newstand she finds that a huge headline has been splashed across the cover page (again, without consulting her... or us, if we have been involved...) saying "[Name] discovers she is a hermaphrodite."
When medicine eventually realised that the mis-alignment type of condition described earlier was a somewhat different situation to the very rare one in which the actual chromosomes and gonadal tisue are a male/female mix, the term for the latter situation was adjusted, from 'hermaphrodite' to 'true hermaphrodite' (see Related Conditions for more information). This meant that a new variant of the term, i.e. 'pseudo-hermaphrodite', could be introduced to describe the mis-aligment situation. The particular mis-alignment where you have XY --> testes --> female appearance (sometimes referred to nowadays as an 'XY female' condition) was charmingly termed 'male pseudo-hermaphrodite' (and there is also a type of condition that comes under the umbrella term 'female pseudo-hermaphrodite'; Congenital Adrenal Hyperplasia for example).
The problems this causes...
Most of our members detest these hermaphrodite terms, just as those with AIS find the old name (testicular feminisation syndrome) for their specific condition deeply offensive. For many of our members who have not been told the truth by doctors, it is these terms that they come across in medical libraries/bookshops, when searching for information that will allow them to make sense of their situation. This is deeply traumatising for a teenager who in all respects except for her internal organs appears to be female (and who often has only come to medical attention through a failure to menstruate) and we feel these archaic terms should be banned from the medical literature.
Jeffrey Eugenides, in his novel Middlesex, was wrong in referring to his main character Callie as a hermaphrodite - something that the press, needless to say, picked up and propagated in their reviews of the book (see AIS in Books/Articles). If he was going to use these out-of-date and confusing terms then Callie (like the vast majority of our members with AIS, 5-alpha-reductase deficiency, Swyers syndrome etc.) was not a hermaphrodite (i.e a true hermaphrodite) but a 'male pseudo-hermaphrodite'. As mentioned above, this is an umbrella term for someone with certain male characteristics (XY sex chromosomes, internal testes) yet certain female characteristics (female external genitalia and general body form, breasts etc.). But this is splitting hairs for most people, and rather than use either archaic term, it would have been much better if Eugenides had just used the more up-to-date term, 'intersex'.
There was a proposal (2006), arising out of a conference involving clinicians and a very limited number of patient support/advocacy groups (ISNA and one European group), to adopt the term Disorders of Sex Development (DSD) as a new term to replace 'intersex'; with the various 'hermaphrodite' terms being replaced with Sex Chromosome DSD (in place of true hermaphrodite), 46,XY DSD (in place of male pseudo-hermaphrodite) and 46,XX DSD (in place of female pseudo-hermaphrodite).
For further information see a) the 2005 scientific paper (by Alice Dreger, Cheryl Chase and others) on changing the nomenclature/taxonomy referenced at the foot of this page, b) the web site of the Consortium on the Management of Disorders of Sex Development (DSDs) accessible via the Links to Other Sites page, and c) the Chicago Conference (Intersex Consensus Meeting) on the Raising Awareness page.
The DSD initiative was largely a US enterprise. The Consortium says that its publications "incorporate the contributions of experts and stakeholders, including medical professionals, social workers, activists, parents and adults with DSDs". However, patient support/advocacy groups outside the USA were not, on the whole, consulted and had no input (see Announcements).
So AIS is a condition that affects the development of the reproductive and genital organs.
Male foetuses usually have a Y sex chromosome which initiates the formation of testes (and the suppression of female internal organ development) during gestation. Testes are the site of production of masculinizing hormones (androgens) in large quantities.
Both male and female foetuses usually have at least one X sex chromosome, which contains a gene that gives their body tissues the capacity to recognise and react to androgens. At puberty girls react to the relatively small quantity of androgens (that come mainly from their adrenal glands) by developing pubic/underam hair and darkish pigmentation around the nipples.
People with AIS have a functioning Y sex chromosome (and therefore no female internal organs), but an abnormality on the X sex chromosome that renders the body completely or partially incapable of recognising the androgens produced. In the case of complete androgen insensitivity (CAIS), the external genital development takes a female form. In the case of partial insensitivity (PAIS), the external genital appearance may lie anywhere along the spectrum from male to female. Other related conditions, resulting from changes on different chromosomes, also disrupt the normal pathway of androgen action, resulting again in a feminized phenotype (body form). See Related Conditions.
People with these 'XY conditions' may identify as female, intergendered, or male.
Every foetus, whether genetically male (XY) or female (XX), starts life with the capacity to develop either a male or female reproductive system. All foetuses have non-specific genitals for the first 8 weeks or so after conception. After a few weeks, in an XY foetus (without AIS), the non-specific genitals develop into male genitals under the influence of male hormones (androgens).
In AIS, the child is conceived with male (XY) sex chromosomes. Embryonic testes develop inside the body and start to produce androgens. In AIS, these androgens cannot complete the male genital development due to a rare inability to use the androgens that the testes produce so the development of the external genitals continues along female lines. However, another hormone produced by the foetal testes suppresses the development of female internal organs. Thus a person with AIS has external genitals that in Complete AIS (CAIS) are completely female or in Partial AIS (PAIS) are partially female. Internally, however, there are testes instead of a uterus and ovaries.
So in a genetically male (XY) foetus the active intervention of male hormones (androgens) is needed to produce a fully male system. A female body type with female external genitalia is the basic underlying human form.
In about two thirds of all cases, AIS is inherited from the mother. In the other third there is a spontaneous mutation in the egg. The mother of the foetus, who does not have AIS, but has the genetic error for AIS on one of her X chromosomes, is called a carrier.
There are two forms of the condition: Complete AIS (CAIS) where the tissues are completely insensitive to androgens, and Partial AIS (PAIS) where the tissues are partially sensitive to varying degrees. The condition is actually represented by a spectrum, with CAIS being a single entity at one end of a range of various PAIS manifestations.
Drs. Charmian Quigley and Frank French (The Laboratories for Reproductive Biology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7500, USA) proposed a grading system for the phenotypic features (external appearance) in AIS, modelled on the Prader classification for Congenital Adrenal Hyperplasia (CAH). The scale runs from AIS Grade 1 to Grade 7 with increasing severity of androgen resistance - and hence decreasing masculinization with increasing feminization.
At the CAIS end of the spectrum the outward appearance is completely female (AIS Grades 6/7) and the sex of rearing is invariably female. In PAIS the outward genital appearance can lie anywhere from being almost completely female (Grade 5), through mixed male/female, to completely male (Grade 1); it has been suggested that slight androgen insensitivity might contribute to infertility in some otherwise normal men. Some babies with PAIS may be raised as males but many are re-assigned as female.
|Grade 1||PAIS||Male genitals, infertility|
|Grade 2||PAIS||Male genitals but mildly 'under-masculinized', isolated hypospadias|
|Grade 3||PAIS||Predominantly male genitals but more severely 'under-masculinized' (perineal hypospadias, small penis, cryptorchidism i.e. undescended testes, and/or bifid scrotum)|
|Grade 4||PAIS||Ambiguous genitals, severely 'under-masculinized' (phallic structure that is indeterminate between a penis and a clitoris)|
|Grade 5||PAIS||Essentially female genitals (including separate urethral and vaginal orifices, mild clitoromegaly i.e. enlarged clitoris)|
|Grade 6||PAIS||Female genitals with pubic/underarm hair|
|Grade 7||CAIS||Female genitals with little or no pubic/underam hair|
Before puberty, individuals with Grade 6 or 7 are indistinguishable
Note however that in the study of Hannema et al (2004), 70% of 'CAIS' patients with substitution mutations in the androgen receptor ligand-binding domain had epididymides and vasa deferentia present. These structures develop from the primitive Wolffian ducts under the influence of androgens, once the testes have formed and started to make testosterone, and were in fact more developed than epididymides and vasa deferentia in 'normal' 16 to 20 week-old male fetuses. The researchers suggest that the combination of some slight tissue sensitivity to androgens together with the particularly high levels of testosterone seen in CAIS can stimulate Wolffian duct development/differentiation. They suggest that the classification of androgen insensitivity in such patients should be considered severe [PAIS] rather than complete [CAIS].
The grading scale is described in more detail, with line drawings of the genital appearance, in issue No. 6 of our newsletter which is available as a free sample download file (see Literature).
It is thought not possible to have the complete and partial forms of AIS in the same family unit. In cases where this appears to happen it is probably a case of one sibling having a low grade of partial AIS (e.g. grade 3 in which there will be some masculinization of the genitalia) and the other sibling having a high grade of PAIS (e.g. grade 6 in which the genital appearance will appear female as in the complete form, which is grade 7, but with pubic/underam hair).
Androgen Insensitivity Syndrome, Androgen Resistance Syndrome, Testicular Feminization Syndrome (Testicular Feminisation Syndrome), Feminizing Testes Syndrome (Feminising Testes Syndrome), Male Pseudo-hermaphroditism, Morris's Syndrome (CAIS), Goldberg-Maxwell Syndrome, Reifenstein Syndrome (PAIS), Gilbert-Dreyfus Syndrome (PAIS), Rosewater Syndrome (PAIS), Lubs Syndrome (PAIS).
Other XY conditions with some similarities to AIS: 5 alpha-reductase deficiency, 17 keto-steroid reductase deficiency, XY gonadal dysgenesis (Swyer Syndrome), leydig cell hypoplasia, Denys-Drash Syndrome, Smith-Lemli-Opitz Syndrome. See Related Conditions.
XX conditions with some similarities to AIS: Mayer Rokitansky Kuster Hauser (MRKH) Syndrome, Mullerian dysgenesis, vaginal atresia.
In human somatic (body) cells there are normally 46 chromosomes made up of 23 pairs. 44 of the 46 are called autosomes because they are not thought to determine gender. The other two are called sex chromosomes. Non-AIS males have a relatively large X and a small Y sex chromosome and normal females have two X sex chromosomes.
When the germ, or generative cells, are formed in the body of the adult, these sex chromosomes become separated, so that a sperm carries either a single X or a single Y chromosome, whilst every egg carries a single X chromosome. At conception the new embryo will be XX or XY, according to whether the egg, which is always X, was fertilized by an X-bearing sperm or by a Y-bearing sperm. Thus the sperm controls the genetic sex of the child.
Although the sex of the embryo is determined at the time of conception, anatomical differences don't show until approximately two months later. In this 'indifferent stage' every foetus has the primitive structures necessary for either a male or a female system: there are both Wolffian ducts and Mullerian ducts.
Gonad is the term given to the undifferentiated organ that will later become either a testis an ovary. Testes develop earlier than ovaries. In an XY foetus, the gonads develop into testes. The testes then cause the Wolffian ducts to develop into the rest of the internal male system, and the Mullerian ducts to be suppressed. In an XX foetus, the gonads develop into ovaries, the Mullerian ducts then form the rest of the female internal system and the Wolffian ducts are suppressed.
It is important to understand not only that there is a single primitive structure in the indifferent stage from which the male or the female organs develop, but that, each reproductive organ in either sex has a counterpart in the opposite sex. For example, the penis of the male and the much smaller clitoris of the female both come from the embryonic genital tubercle or phallus. Men have a vestigial uterus, the utriculus masculinus in the prostate and women have a homologue prostate in the glands at the lower end of the urethra.
There are a number of abnormalities of the sex chromosomes that can occur. One example is Klinefelter's Syndrome, in which a man carries an extra X chromosome. Another is Turner Syndrome in which a woman is missing an X chromosome. AIS is not a disorder of the sex chromosomes, because the sex chromosomes in an AIS baby are those of a normal male, XY. The genetic fault lies in the Androgen Receptor (AR) gene on the X chromosome received from the mother. This affects the responsiveness, or sensitivity, of the foetus's body tissues to androgens.
AIS is inherited by a genetic condition in the family known as an X-linked recessive inheritance pattern, or partly recessive gene or a male-limited autosomal dominant. This means that it is passed on via the female line, so it can affect some or all of a mother's XY children. For a carrier woman there is a 1 in 4 risk in each pregnancy of that child having AIS (or a 1 in 2 risk if the foetus of such a pregnancy is known to be genetically male, e.g. as a result of an amniocentesis sample taken during pregnancy). The AIS condition does not manifest in embryos of a carrier mother that are genetically female (i.e. XX) but they have a 1 in 2 chance of being carriers themselves and could therefore pass AIS on to their children.
So the possibilities in a given pregnancy, where the mother is a carrier, are...
'Normal' XY boy, or
AIS XY baby, or
'Normal' XX girl, or
Carrier XX girl
... with a 1 in 4 chance of each situation resulting.
If AIS is present in a family, there are tests available to see if an XX woman is a carrier and thus capable of passing the defective gene on to her children (see Obtaining/Facing Diagnosis).
In the case of an AIS foetus, a Y-bearing sperm fertilizes the egg (which is always X) and produces an XY embryo. In the early stage of foetal life differentiation is as a male, with testes and the Mullerian ducts regressing. The Mullerian ducts would have formed the internal female organs in an XX girl. Once the testes are formed, they start to produce testosterone, which would normally cause the masculinization of the body.
Masculinization is an active process; it needs the positive or active intervention of the male hormones in order to take place. If these male hormones are either absent, or the tissues do not respond to them (as happens to differing degrees in the various forms of AIS), then the passive tendency is for the external genitals to differentiate into female external organs which, in the complete form of AIS, are indistinguishable from those of normal girls. This female physical development is not due to the presence and influence of oestrogens but to the ineffectiveness of androgens . In other words, the inherent trend is for any foetus to develop female external genitals and general body form, in the absence of the masculinizing effects of male hormones. Or as Money et al express it "Cellular insensitivity to androgen (in AIS) permits the 46,XY foetus not to masculinize." Shearman is somewhat more dramatic in his declaration that "If the target cells lack this (androgen) receptor, testosterone passes like a stranger in the night and neutral female absolutism reigns supreme."
Unfortunately, however, by the time the androgen insensitivity in AIS becomes evident, the internal reproductive organs have already progressed partially down the male route, and the Mullerian Inhibitory Factor (MIF) from the testes has already begun its work of destroying the primitive female internal organs. The testes remain in a 'frozen' partially-developed male state and the development of the internal female organs cannot be reactivated.
Mainly using data on the frequency of inguinal (groin) hernia in presumed females, Jagiello and Atwell estimated the frequency of AIS to be about 1 in 65,000 genetic males. This presumably refers only to the complete form (CAIS), since the infants were assumed to be female until the occurrence of the hernia. DeGroot quotes an incidence of about 1 in 60,000. Hauser gives an incidence of 1 in 2,000. Adams-Smith et al give a figure of 1 in 20,000. The most accurate figure currently available is probably that from an analysis (Bangsboll et al.) of a nationwide Danish patient register, suggesting an incidence of 1 in 20,400 male births (hospitalized cases only, so the true incidence is probably higher). CAIS has been said to rank third as a cause of primary amenorrhoea (lack of menstruation), after gonadal dysgenesis (Turner Syndrome) and congenital absence of the vagina (Mayer-Rokitansky-Kuster-Hauser syndrome).
Complete AIS (CAIS) is sometimes referred to as 'classical testicular feminization' ('classical testicular feminisation'), CAIS may be more common than PAIS (the 'partial' form of the condition) but we don't have incidence figures for PAIS.
A condition that could have been AIS was mentioned in the Talmud (400 BC). A speculation has been made that Joan of Arc (1412) might have had AIS. The same suggestion has been made with regard to Queen Elizabeth I, the 'Virgin Queen' (1533 - 1603).
AIS may have been reported as early as 1817, when Steglehner described the case of an apparently normal woman who had undescended testes. The condition has been of relatively long interest to geneticists. Dieffenbach, an American geneticist, first pointed out in 1906 that there is a hereditary pattern to AIS. Petterson and Bonnier (1937) concluded that the affected persons are genetically male. Some early textbooks refer to the syndrome as the Goldberg-Maxwell Syndrome. Morris (1953) first used the term "testicular feminization." Morris and Mahesh (1963) subsequently described an incomplete form of the condition.
Wilkins (1957) first demonstrated that the basic defect is tissue unresponsiveness to androgens. Hence the newer, and as far as most clinicians are concerned, more correct name of Androgen Insensitivity Syndrome. Netter and colleagues (1958) reported this disorder in a famous photographic model and Marshall and Harder (1958) reported affected twins who worked as airline stewardesses. In 1974 Migeon showed that the condition results from androgen receptor resistance. The androgen receptor gene was cloned and sequenced in 1988.
See Medical Literature Sites on our 'Links to Other Sites' page for ways of accessing journal articles.
Money J., Schwartz M., Lewis V.G: Adult erotosexual status and fetal hormonal masculinization and demasculinization: 46,XX congenital virilizing adrenal hyperplasia and 46,XY androgen-insensitivity syndrome compared. Psychoneuroendocrinology, Vol 9, No 4, pp 405-414, 1984.
Shearman R.P: Intersexuality. In Clinical Reproductive Endocrinology, Churchill Livingstone, p346-361, 1985.
Jagiello F. and Atwell J.D.: Prevalence of testicular feminization. Lancet I: 329 only, 1962.
DeGroot L.J. (ed): Endocrinology, Vol 2 (Ed 2), Philadelphia PA, Saunders, 1989.
Hauser G. A: Testicular Feminization. In Intersexuality. Edited by C. Overzier. Academic Press, New York, 1963.
Adams-Smith W.N. and Peng M.T: Inductive influence of testosterone upon central sexual maturation in the rat. J. Embryol. Morph., 17: 171, 1967.
Bangsboll S et al: Testicular feminization syndrome and associated tumours in Denmark. Acta Obstet Gynecol Scand 71:63-66, 1992.
Griffin J.E.. Wilson J.D: The syndromes of androgen resistance. N. Engl. J. Med. 1980; 302: 198-209.
Wooster N: The Real Joan of Arc?, published by The Book Guild, Lewes, Sussex (1992?). The statement in this book, that Bernard Shaw's heroine may have had testicular feminization, is discussed in a letter from G. Richeux, Doncaster, to The Guardian on 4 September 1992 and entitled "Oh why can't a woman be more like an admirable, literary man?".
Queen Elizabeth I: A Case of Testicular Feminization Syndrome? Med. Hypotheses, 1985, 17, 277-84.
Steglehner G: De Hermaphroditism Nature. Kunz Bambergae et Lipsias, 1817.
Dieffenbach H.: Familiaerer Hermaphroditismus. Inaugural Dissertation, Stuttgart, 1912.
Petterson G. and Bonner G.: Inherited sex-mosaic in man. Hereditas 23: 49-69, 1937.
Goldberg M.B., Maxwell A.F.: Male pseudohermaphroditism proved by surgical exploration and microscopic examination. A case report with speculations regarding pathogenesis. J. Clin. Endocrinol. 8:367-379, 1948.
Morris J: The syndrome of testicular feminization in male pseudohermaphrodites. Am. J. Obstet. Gynecol, 65: 1192-1211, 1953.
Morris J.M. and Mahesh V. B: Further observations on the syndrome, `testicular feminization'. Am. J. Obstet. Gynec. 87: 731-748, 1963.
Wilkins L: The Diagnosis and Treatment of Endocrine Disorders in Childhood and Adolescence. Springfield, III: Charles C. Thomas, 1957 (2nd ed.).
Netter A., Lumbrosa P., Yaneva H and Liddle J: Le testicule feminisant. Ann. Endocr. 19: 994-1014, 1958.
Marshall H.K. and Harder H.I: Testicular feminizing syndrome in male pseudohermaphrodite: report of two cases in identical twins. Obstet. Gynec. 12:284-293, 1958.
Migeon et al.: Studies of the locus for androgen receptor:localization on the human X and evidence for homology with the Tfm locus in the mouse. Proc. Nat. Acad. Sci. 78: 6339-6343, 1981.
Boehmer A.L. et al: Genotype versus phenotype in families with androgen insensitivity syndrome. J. Clin. Endoc. and Metab., 2001; 86: 4151-60.
Wilson Bruce E: Androgen Insensitivity Syndrome. A useful online monograph covering many aspects of AIS. Dr. Wilson has been mentioned a number of times in our newsletter, ALIAS, and has spoken at AISSG US group meetings.
Hannema S.E., ScottIan S., Hodapp J., Martin H., Coleman N., Schwabe J.W. and Hughes I.A: Residual Activity of Mutant Androgen Receptors Explains Wolffian Duct Development in the Complete Androgen Insensitivity Syndrome. J. Clin. Endoc. and Metab., Vol. 89, No. 11, 5815-5822 (2004).
Minto C. L. et al: XY Females: Revisiting the Diagnosis. BJOG (an International Journal of Obstetrics and Gynaecology), Vol. 112, pp. 1407-1410, October 2005.
Dreger A. D. et al: Changing the Nomenclature/Taxonomy for Intersex: A Scientific and Clinical Rationale. Journal of Pediatric Endocrin. & Metab., 18: 729-733 (2005).