Vickie Pasterski

Androgen insensitivity syndrome

Androgen insensitivity syndrome in its complete form is a disorder of hormone resistance characterised by a female phenotype in an individual with an XY karyotype and testes producing age-appropriate normal concentrations of androgens. Pathogenesis is the result of mutations in the X-linked androgen receptor gene, which encodes for the ligand-activated androgen receptor--a transcription factor and member of the nuclear receptor superfamily. This Seminar describes the clinical manifestations of androgen insensitivity syndrome from infancy to adulthood, reviews the mechanism of androgen action, and shows examples of how mutations of the androgen receptor gene cause the syndrome. Management of androgen insensitivity syndrome should be undertaken by a multidisciplinary team and include gonadectomy to avoid gonad tumours in later life, appropriate sex-hormone replacement at puberty and beyond, and an emphasis on openness in disclosure.

Spatial abilities following prenatal androgen abnormality: targeting and mental rotations performance in individuals with congenital adrenal hyperplasia.

In most mammals, behaviors that show sex differences are influenced by androgen during early life. In the current study, the hypothesis that androgen influences the development of human spatial abilities was investigated. Participants included 40 females and 29 males with congenital adrenal hyperplasia (CAH), a genetic disorder that causes overproduction of adrenal androgens beginning prenatally, and 29 unaffected female and 30 unaffected male relatives of individuals with CAH. Participants ranged in age from 12-45 years. Measures of spatial abilities included two mental rotations tasks and two targeting tasks, all of which showed large sex differences favoring males in the unaffected relative controls. Females with CAH (exposed to higher than normal levels of androgen prenatally) performed better than unaffected females on the targeting tasks, and resembled unaffected males and males with CAH in this respect. However, females with CAH did not perform better than unaffected females on the measures of mental rotations abilities. Males with CAH showed unaltered performance on the targeting tasks, and impaired performance on the mental rotations tasks. Results are discussed in terms of differences in experiential and hormonal contributions to different spatial abilities, as well as in terms of possible differences in critical periods for hormonal influences on targeting versus mental rotations abilities. Specifically, we speculate that, although androgen may influence targeting abilities prenatally, if hormones influence the development of mental rotations ability, they do so at some other time, perhaps during the first six months of postnatal life.

Increased aggression and activity level in 3- to 11-year-old girls with congenital adrenal hyperplasia (CAH).

Experimental research in a wide range of mammals has documented powerful influences of androgen during early development on brain systems and behaviors that show sex differences. Clinical research in humans suggests similar influences of early androgen concentrations on some behaviors, including childhood play behavior and adult sexual orientation. However, findings have been inconsistent for some other behaviors that show sex differences, including aggression and activity level in children. This inconsistency may reflect small sample sizes and assessment limitations. In the present study, we assessed aggression and activity level in 3- to 11-year-old children with CAH (38 girls, 29 boys) and in their unaffected siblings (25 girls, 21 boys) using a questionnaire that mothers completed to indicate current aggressive behavior and activity level in their children. Data supported the hypotheses that: (1) unaffected boys are more aggressive and active than unaffected girls; (2) girls with CAH are more aggressive and active than their unaffected sisters; and (3) boys with and without CAH are similar to one another in aggression and activity level. These data suggest that early androgens have a masculinizing effect on both aggressive behavior and activity level in girls.

Consequences of the Chicago consensus on disorders of sex development (DSD): current practices in Europe

Objective To assess clinical management of disorders of sex development (DSD) subsequent to recommendations issued in the 2006 Consensus Statement. Design Online questionnaire and audit of DSD literature. Setting Invitation to complete a 28-item online questionnaire and a 12-item follow-up questionnaire, both assessing current clinic statistics and clinical management of DSD. Participants Paediatric endocrinologists from 60 medical centres representing 23 European countries. Main outcome measures Clinic activity, multidisciplinary team composition, provision of psychological support services, incidence of feminising clitoroplasty and use of diagnostic algorithms and newly proposed nomenclature. Analyses Data are reported in terms of percentages with respect to implementation of recommendations outlined in the Consensus Statement. χ2 was used to analyse changes in nomenclature reported in the literature. Results 60 centres reported on management of an average of 97.3 (range 8–374) patients per year, totalling approximately 6000. The mean number of new referrals in the previous year was 23.27 (range 8–100). 57% of centres regularly included the services of recommended paediatric subspecialists: paediatric endocrinologist, paediatric surgeon/urologist, plastic surgeon, paediatric psychiatrist/psychologist, gynaecologist, clinical geneticist, histopathologist and neonatologist; 35% reported providing these and additional services of endocrine and surgical nurses, a social worker and a medical ethicist. Additionally, 95% of centres reported offering primary psychological support services (either child psychiatrist or psychologist). 65% of centres reported using a diagnostic algorithm, and 83.3% supported the development of a standardised algorithm. 52% and 44.8% of centres reported having performed fewer or similar numbers, respectively, of clitoroplasties than in previous years and only 3.4% reported an increase. Finally, 100% of respondents reported using the newly proposed terminology. Likewise, an audit of the literature reflected a recent reduction in usage of the non-preferred historical terminology. Conclusions There is evidence that the majority of European DSD centres have implemented policies and procedures in accordance with the recommendations issued by the 2006 Consensus Group. These findings represent a change in practice with the collaborative goal of improved patient care.

Androgenic influences on neural asymmetry: Handedness and language lateralization in individuals with congenital adrenal hyperplasia

This study tested the hypothesis that prenatal androgen levels influence hand preferences and language lateralization, two manifestations of neural asymmetry. Participants were individuals with congenital adrenal hyperplasia (CAH, a genetic disorder that results in excess adrenal androgen production beginning prenatally) (40 females; 29 males) and their unaffected relatives (29 females; 30 males) who ranged in age from 12-45 years. The Edinburgh-Crovitz Inventory and the performance of five simple tasks (the Handedness Activities Test) were the measures of hand preferences, and a dichotic listening task composed of consonant-vowel nonsense syllables was the measure of language lateralization. No sex differences were observed among relative controls in hand preferences or language lateralization. Male participants with CAH were less consistently right-handed for writing than unaffected male relatives, when those who had been forced to switch writing hands from left to right were considered with left-handers as being not consistently right-handed. There were no other significant differences between individuals with CAH and unaffected relatives. These results do not support the hypothesis that prenatal androgens influence language lateralization, nor do they support the Geschwind-Behan-Galaburda model that posits a key role for testosterone in the development of cognitive problems in males, secondary to changes in hemispheric development and cognitive lateralization. Hormonal influences on handedness, although not always consistent, may be more likely. However, given that sex differences in both language lateralization and handedness are small, it is possible that limited sample size precludes the detection of consistent group differences.

Prenatal hormones and childhood sex segregation: Playmate and play style preferences in girls with congenital adrenal hyperplasia

We investigated playmate and play style preference in children with congenital adrenal hyperplasia (CAH) (26 females, 31 males) and their unaffected siblings (26 females, 17 males) using the Playmate and Play Style Preferences Structured Interview (PPPSI). Both unaffected boys and girls preferred same-sex playmates and sex-typical play styles. In the conflict condition where children chose between a same-sex playmate engaged in an other-sex activity or an other-sex playmate engaged in a same-sex activity, boys (both CAH and unaffected brothers) almost exclusively chose playmates based on the preferred play style of the playmate as opposed to the preferred gender label of the playmate. By contrast, unaffected girls used play style and gender label about equally when choosing playmates. Girls with CAH showed a pattern similar to that of boys: their playmate selections were more masculine than unaffected girls, they preferred a boy-typical play style and, in the conflict condition, chose playmates engaged in a masculine activity. These findings suggest that prenatal androgen exposure contributes to sex differences in playmate selection observed in typically developing children and that, among boys and girls exposed to high levels of androgens prenatally, play style preferences drive sex segregation in play.

Anogenital distance as a marker of androgen exposure in humans.

Abnormal foetal testis development has been proposed to underlie common disorders of the male reproductive system such as cryptorchidism, hypospadias, reduced semen quality and testicular germ cell tumour, which are regarded as components of a ‘testicular dysgenesis syndrome’. The increasing trends and geographical variation in their incidence have been suggested to result from in utero exposure to environmental chemicals acting as endocrine disruptors. In rodents, the anogenital distance (AGD), measured from the anus to the base of genital tubercle, is a sensitive biomarker of androgen exposure during a critical embryonic window of testis development. In humans, several epidemiological studies have shown alterations in AGD associated with prenatal exposure to several chemicals with potential endocrine disrupting activity. However, the link between AGD and androgen exposure in humans is not well‐defined. This review focuses on the current evidence for such a relationship. As in rodents, a clear gender difference is detected during foetal development of the AGD in humans which is maintained thereafter. Reduced AGD in association with clinically relevant outcomes of potential environmental exposures, such as cryptorchidism or hypospadias, is in keeping with AGD as a marker of foetal testicular function. Furthermore, AGD may reflect variations in prenatal androgen exposure in healthy children as shorter AGD at birth is associated with reduced masculine play behaviour in preschool boys. Several studies provide evidence linking shorter AGD with lower fertility, semen quality and testosterone levels in selected groups of adults attending andrology clinics. Overall, the observational data in humans are consistent with experimental studies in animals and support the use of AGD as a biomarker of foetal androgen exposure. Future studies evaluating AGD in relation to reproductive hormones in both infants and adults, and to gene polymorphisms, will help to further delineate the effect of prenatal and postnatal androgen exposures on AGD.

Postnatal penile growth concurrent with mini-puberty predicts later sex-typed play behavior: Evidence for neurobehavioral effects of the postnatal androgen surge in typically developing boys

The masculinizing effects of prenatal androgens on human neurobehavioral development are well established. Also, the early postnatal surge of androgens in male infants, or mini-puberty, has been well documented and is known to influence physiological development, including penile growth. However, neurobehavioral effects of androgen exposure during mini-puberty are largely unknown. The main aim of the current study was to evaluate possible neurobehavioral consequences of mini-puberty by relating penile growth in the early postnatal period to subsequent behavior. Using multiple linear regression, we demonstrated that penile growth between birth and three months postnatal, concurrent with mini-puberty, significantly predicted increased masculine/decreased feminine behavior assessed using the Pre-school Activities Inventory (PSAI) in 81 healthy boys at 3 to 4years of age. When we controlled for other potential influences on masculine/feminine behavior and/or penile growth, including variance in androgen exposure prenatally and body growth postnally, the predictive value of penile growth in the early postnatal period persisted. More specifically, prenatal androgen exposure, reflected in the measurement of anogenital distance (AGD), and early postnatal androgen exposure, reflected in penile growth from birth to 3months, were significant predictors of increased masculine/decreased feminine behavior, with each accounting for unique variance. Our findings suggest that independent associations of PSAI with AGD at birth and with penile growth during mini-puberty reflect prenatal and early postnatal androgen exposures respectively. Thus, we provide a novel and readily available approach for assessing effects of early androgen exposures, as well as novel evidence that early postnatal aes human neurobehavioral development.

Are There Parental Socialization Effects on the Sex-Typed Behavior of Individuals with Congenital Adrenal Hyperplasia?

Influences of prenatal androgen exposure on human sex-typical behavior have been established largely through studies of individuals with congenital adrenal hyperplasia (CAH). However, evidence that addresses the potential confounding influence of parental socialization is limited. Parental socialization and its relationship to sex-typical toy play and spatial ability were investigated in two samples involving 137 individuals with CAH and 107 healthy controls. Females with CAH showed more boy-typical toy play and better targeting performance than control females, but did not differ in mental rotations performance. Males with CAH showed worse mental rotations performance than control males, but did not differ in sex-typical toy play or targeting. Reported parental encouragement of girl-typical toy play correlated with girl-typical toy play in all four groups. Moreover, parents reported encouraging less girl-typical, and more boy-typical, toy play in females with CAH than in control females and this reported encouragement partially mediated the relationship between CAH status and sex-typical toy play. Other evidence suggests that the reported parental encouragement of sex-atypical toy play in girls with CAH may be a response to the girls’ preferences for boys’ toys. Nevertheless, this encouragement could further increase boy-typical behavior in girls with CAH. In contrast to the results for toy play, we found no differential parental socialization for spatial activities and little evidence linking parental socialization to spatial ability. Overall, evidence suggests that prenatal androgen exposure and parental socialization both contribute to sex-typical toy play.

Prenatal androgen exposure alters girls' responses to information indicating gender-appropriate behaviour

Individual variability in human gender-related behaviour is influenced by many factors, including androgen exposure prenatally, as well as self-socialization and socialization by others postnatally. Many studies have looked at these types of influences in isolation, but little is known about how they work together. Here, we report that girls exposed to high concentrations of androgens prenatally, because they have the genetic condition congenital adrenal hyperplasia, show changes in processes related to self-socialization of gender-related behaviour. Specifically, they are less responsive than other girls to information that particular objects are for girls and they show reduced imitation of female models choosing particular objects. These findings suggest that prenatal androgen exposure may influence subsequent gender-related behaviours, including object (toy) choices, in part by changing processes involved in the self-socialization of gendered behaviour, rather than only by inducing permanent changes in the brain during early development. In addition, the findings suggest that some of the behavioural effects of prenatal androgen exposure might be subject to alteration by postnatal socialization processes. The findings also suggest a previously unknown influence of early androgen exposure on later processes involved in self-socialization of gender-related behaviour, and thus expand understanding of the developmental systems regulating human gender development.