Studiensammlung: Complete androgen insensitivity syndrome (CAIS)

1. Psychological Outcomes and Gender-Related Development in Complete Androgen Insensitivity Syndrome

We evaluated psychological outcomes and gender development in 22 women with complete androgen insensitivity syndrome (CAIS). Participants were recruited through a medical database (n = 10) or through a patient support group (n = 12). Controls included 14 males and 33 females, of whom 22 were matched to women with CAIS for age, race, and sex-of-rearing. Outcome measures included quality of life (self-esteem and psychological general well-being), gender-related psychological characteristics (gender identity, sexual orientation, and gender role behavior in childhood and adulthood), marital status, personality traits that show sex differences, and hand preferences. Women recruited through the database versus the support group did not differ systematically, and there were no statistically significant differences between the 22 women with CAIS and the matched controls for any psychological outcome. These findings argue against the need for two X chromosomes or ovaries to determine feminine-typical psychological development in humans and reinforce the important role of the androgen receptor in influencing masculine-typical psychological development. They also suggest that psychological outcomes in women with CAIS are similar to those in other women. However, additional attention to more detailed aspects of psychological well-being in CAIS is needed.

2. Complete Androgen Insensitivity Syndrome: Long-Term Medical, Surgical, and Psychosexual Outcome

Controversy concerning the most appropriate treatment guidelines for intersex children currently exists. This is due to a lack of long-term information regarding medical, surgical, and psychosexual outcome in affected adults. We have assessed by questionnaire and medical examination the physical and psychosexual status of 14 women with documented complete androgen insensitivity syndrome (CAIS). We have also determined participant knowledge of CAIS as well as opinion of medical and surgical treatment. As a whole, secondary sexual development of these women was satisfactory, as judged by both participants and physicians. In general, most women were satisfied with their psychosexual development and sexual function. Factors reported to contribute to dissatisfaction were sexual abuse in one case and marked obesity in another. All of the women who participated were satisfied with having been raised as females, and none desired a gender reassignment. Although not perfect, the medical, surgical, and psychosexual outcomes for women with CAIS were satisfactory; however, specific ways for improving long-term treatment of this population were identified.

3. Neural Activation During Mental Rotation in Complete Androgen Insensitivity Syndrome: The Influence of Sex Hormones and Sex Chromosomes

Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY, have not been well studied in humans. Individuals with complete androgen insensitivity syndrome (CAIS), who have a 46,XY karyotype but a female phenotype due to a complete androgen resistance, enable us to study the separate effects of gonadal hormones versus sex chromosomes on neural sex differences. Therefore, in the present study, we compared 46,XY men (n = 30) and 46,XX women (n = 29) to 46,XY individuals with CAIS (n = 21) on a mental rotation task using functional magnetic resonance imaging. Previously reported sex differences in neural activation during mental rotation were replicated in the control groups, with control men showing more activation in the inferior parietal lobe than control women. Individuals with CAIS showed a female-like neural activation pattern in the parietal lobe, indicating feminization of the brain in CAIS. Furthermore, this first neuroimaging study in individuals with CAIS provides evidence that sex differences in regional brain function during mental rotation are most likely not directly driven by genetic sex, but rather reflect gonadal hormone exposure.

4. Androgen Insensitivity Syndrome: Somatic Mosaicism of the Androgen Receptor in Seven Families and Consequences for Sex Assignment and Genetic Counseling 

Androgen insensitivity syndrome (AIS) is caused by numerous mutations of the androgen receptor (AR) gene. The phenotype may range from partial AIS (PAIS) with ambiguous genitalia to complete AIS (CAIS) with female genitalia. In 70% of the cases, AR mutations are transmitted in an X-linked recessive manner through the carrier mothers, but in 30%, the mutations arise de novo. When de novo mutations occur after the zygotic stage, they result in somatic mosaicisms, which are an important consideration for both virilization in later life—because both mutant and wild-type receptors are expressed—and genetic counseling. We report here six patients with AIS due to somatic mutations of the AR and one mother with somatic mosaicism who transmitted the mutation twice. Of the four patients with PAIS, three presented spontaneous or induced virilization at birth or puberty. These cases underline the crucial role of the remnant wild-type AR for virilization because the same mutations, when they are inherited, lead to CAIS. We also report two novel mutations of the AR, with somatic mosaicism, detected in patients with CAIS. Thus, the remnant wild-type receptor does not always lead to virilization. In one of these patients, a high ratio of wild-type to mutant AR expression was found in the gonads and genital skin fibroblasts. Although no prenatal virilization occurred, the possibility of virilization at puberty could not be excluded, and early gonadectomy was performed. A seventh patient had a CAIS with a novel germline AR mutation. The mutation was inherited from the mother, in whom mosaicism was detected in blood and who transmitted the mutation to a second, XX, offspring. The detection of somatic AR mutations is particularly important for the clinical management and genetic counseling of patients with AIS. Before definite sex assignment, a testosterone treatment trial should be performed in all patients with PAIS, but it becomes crucial when an AR mosaicism has been detected. In patients with CAIS or severe PAIS raised as female, there is no consensus about when (early childhood or puberty) gonadectomy should be performed. When somatic AR mutations are detected, however, gonadectomy should be performed earlier because of the risk of virilization during puberty. When a germline de novo mutation is identified in the index case, the risk of transmission to a second child due to a possible germ cell mosaicism in the mother cannot be excluded. However, given the high number of AR de novo mutations and the rarity of such reports, this risk appears to be very low.

5. Sexual orientation and medical history among Iranian people with complete androgen insensitivity syndrome and congenital adrenal hyperplasia

To report sexual orientation, relationship status and medical history of Iranian people with Differences of Sex Development (DSD) who were raised female.
Our participants consisted of nineteen 46,XY individuals with Complete Androgen Insensitivity Syndrome (CAIS) and eighteen 46,XX individuals with Congenital Adrenal Hyperplasia (CAH) who were raised as females and older than 13 years. As well as their relationship status and detailed medical history, an expert psychiatrist assessed their sexual orientation by a semi-structured psychiatric interview with them and, where applicable, their parents.
Five percent of CAH participants and 42% of CAIS participants were in a relationship, which was significantly different. All CAH individuals had been diagnosed at birth; 89% of CAIS had been diagnosed after puberty and due to primary amenorrhea and 11% were diagnosed in childhood due to inguinal hernia. Genital reconstructive surgery had been performed in 100% of CAH participants and 37% of CAIS. Regarding sexual contact experiences and sexual fantasies (androphilic, gynephilic or both), no significant differences were found. However, CAH females had significantly more gynephilic dreams (P = 0.045).
This study, notable as one of the rare from a non-western culture, described sexual, medical and socioeconomic status of 46,XX CAH and 46,XY CAIS individuals living in Iran. Although broadly in line with previous findings from Western cultures, Iranian CAH individuals had fewer romantic relationships, but in contrast to previous studies their sexual orientation was only different from CAIS in the contents of sexual dreams.