Maria I. New

Disease expression and molecular genotype in congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

Genotyping for 10 mutations in the CYP21 gene was performed in 88 families with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Southern blot analysis was used to detect CYP21 deletions or large gene conversions, and allele-specific hybridizations were performed with DNA amplified by the polymerase chain reaction to detect smaller mutations. Mutations were detected on 95% of chromosomes examined. The most common mutations were an A----G change in the second intron affecting pre-mRNA splicing (26%), large deletions (21%), Ile-172----Asn (16%), and Val-281----Leu (11%). Patients were classified into three mutation groups based on degree of predicted enzymatic compromise. Mutation groups were correlated with clinical diagnosis and specific measures of in vivo 21-hydroxylase activity, such as 17-hydroxyprogesterone, aldosterone, and sodium balance. Mutation group A (no enzymatic activity) consisted principally of salt-wasting (severely affected) patients, group B (2% activity) of simple virilizing patients, and group C (10-20% activity) of nonclassic (mildly affected) patients, but each group contained patients with phenotypes either more or less severe than predicted. These data suggest that most but not all of the phenotypic variability in 21-hydroxylase deficiency results from allelic variation in CYP21. Accurate prenatal diagnosis should be possible in most cases using the described strategy.

Effects of early prenatal dexamethasone on the cognitive and behavioral development of young children: Results of a pilot study

The effect of early prenatal dexamethasone (DEX) exposure on cognitive and behavioral development, behavior problems, and temperament were examined in 26 consecutively identified children aged 6 mo to 5 1/2 years, whose mothers had been DEX-treated during pregnancy because their offspring was at risk for congenital adrenal hyperplasia (CAH), and compared with 14 children from untreated CAH-risk pregnancies. Three children in each group were CAH-affected. Assessments were performed by way of mother-completed standard questionnaires. No significant differences in cognitive abilities or behavior problems were identified. On temperament questionnaires, DEX-exposed children showed more Shyness (p < .004), greater Emotionality (p < .03), less Sociability (p < .04), and a trend for greater Avoiddance (p < .07) than unexposed children. DEX-exposed children also had significantly higher Internalizing (p < .002) and Total Problem scores (p < .05) on the behavior problem measure for 2-3 year olds. The results should be considered preliminary until they have been replicated by the study of a larger sample and direct examination of the children.

Genetic Mapping of the 21-Hydroxylase-Deficiency Gene within the HLA Linkage Group

To document further the proposed genetic linkage between congenital adrenal hyperplasia due to 21-hydroxylase deficiency and HLA, 34 unrelated families from New York and Zurich, with a total of 48 patients, 48 siblings and their parents, were studied. All patients were HLA genotypically different from the healthy sibs; when two or more children were affected in the same sibship they were always HLA-B identical. The gene for 21-hydroxylase deficiency was separated by genetic recombination from the HLA-A locus and from the locus for glyoxalase I-polymorphism. No HLA-A, HLA-B or HLA-C antigen was selectively increased among the 34 unrelated patients. Lod-score analysis for HLA-B:21-hydroxylase deficiency gave a peak for theta approximately 0.00 at 5.20 for females and 4.30 for males, giving a total peak lod score of 9.5 at theta approximately 0.00 when male and female lod scores were combined. Close genetic linkage between HLA-B and 21-hydroxylase deficiency was thus established.

An Update of Congenital Adrenal Hyperplasia

Abstract: Congenital adrenal hyperplasia (CAH) is a family of autosomal recessive disorders caused by mutations that encode for enzymes involved in one of the various steps of adrenal steroid synthesis. These defects result in the absence or the decreased synthesis of cortisol from its cholesterol precursor. The anterior pituitary secretes excess adrenocorticotrophic hormone (ACTH) via feedback regulation by cortisol, which results in overstimulation of the adrenals and causes hyperplasia. Symptoms due to CAH can vary from mild to severe depending on the degree of ensymatic defect. In the classical form of CAH, there is a severe enzymatic defect owing to mutations in the CYP21 gene. Classically affected female fetuses undergo virilization of the genitalia prenatally and present with genital ambiguity at birth; however, prenatal treatment of CAH with dexamethasone to prevent ambiguity has been successfully utilized for over a decade. In the less severe, late‐onset form of CAH, prenatal virilization does not occur. The milder enzyme deficiency was termed nonclassical 21‐hydroxylase deficiency (NC21OHD) in 1979 and was later found to be the most common autosomal recessive disorder in humans. Disease frequency of NC21OHD varies between ethnic groups with the highest ethnic‐specific disease frequency in Ashkenazi Jews at 1/27. NC21OHD is diagnosed by serum elevations of 17‐OHP that plot on a nomogram between the range for unaffected individuals and levels observed for classical CAH and is typically confirmed with molecular genetic analysis. Similar to classical CAH, nonclassical 21‐hydroxylase deficiency may cause premature development of pubic hair, advanced bone age, acelerated linear growth velocity and diminished final height in both males and females. Severe cystic acne has also been attributed to nonclassical CAH. Women may present with symptoms of androgen excess, including hirsutism, temporal baldness, and infertility. Menarche in females may be normal or delayed and secondary amenorrhea is a frequent occurence. Polycystic ovary syndrome may also be seen in these patients. In males, early beard growth, acne, and growth spurt may prompt the diagnosis of NC21OHD. Although many males appear to be asymptomatic, they may present with oligozoospermia or diminished fertility. Individuals presenting to dermatology and infertility clinics with symptoms of hyperandrogenemia are rarely screened for NC21OHD. However, with hormonal and molecular genetic screening, previously undiagnosed patients may be identified and can therefore receive glucocorticoid treatment, which has been shown to reverse symptoms within 3 months.

Gender Change from Female to Male in Classical Congenital Adrenal Hyperplasia

The psychoendocrinology of the development of normal gender identity and its variations is poorly understood. Studies of gender development in individuals born with endocrinologically well-characterized intersex conditions are heuristically valuable for the disaggregation of factors that are acting in concert during normal development. Four 46,XX individuals with classical congenital adrenal hyperplasia (CAH) and atypical gender identity entered a comprehensive research protocol including systematic interviews and self-report inventories on gender role behavior and identity, sexual history, and psychiatric history. Some of the data on gender variables were compared to data from 12 CAH women with the salt-wasting variant (CAH-SW) with female gender identity. The four patients (ages 28, 35, 38, and 30 years) represented three different subtypes of classical early-onset CAH: 21-OH deficiency, simple virilizing (CAH-SV); 21-OH deficiency, salt-wasting (CAH-SW); and 11-beta-OH deficiency. Their medical histories were characterized by delay beyond infancy or lack of surgical feminization of the external genitalia and progressive virilization with inconsistent or absent glucocorticoid replacement therapy. Although three patients had undergone one or more genital surgeries, all had retained at least some orgasmic capacity. In regard to childhood gender-role behavior, the four gender-change patients tended to be more masculine or less feminine than (behaviorally masculinized) CAH-SW controls. All patients were sexually attracted to females only. The process of gender change was gradual and extended well into adulthood. The most plausible factors contributing to cross-gender identity development in these patients appeared to be neither a particular genotype or endocrinotype nor a sex-typing bias on the part of the parents but a combination of a gender-atypical behavioral self-image, a gender-atypical body image, and the development of erotic attraction to women. Implications for psychosocial management are also discussed.

Hormones and handedness Left‐hand bias in female congenital adrenal hyperplasia patients

An excess of left-handers among males has been attributed to early androgen exposure. This theory was supported by our observation that girls with congenital adrenal hyperplasia (CAH) are more left-biased than their normal sisters. Male CAH patients, with prenatal androgen exposure similar to that of unaffected brothers, had typical male-handedness patterns.

Prenatal androgenization affects gender-related behavior but not gender identity in 5-12-year-old girls with congenital adrenal hyperplasia.

Gender assignment of children with intersexuality and related conditions has recently become highly controversial. On the basis of extensive animal research and a few human case reports, some authors have proposed the putative masculinization of the brain by prenatal hormones—indicated by the degree of genital masculinization—as the decisive criterion of gender assignment and have derived the recommendation that 46,XX newborns with congenital adrenal hyperplasia (CAH) and full genital masculinization should be assigned to the male gender. The purpose of this study was to test in CAH girls of middle childhood the assumption that prenatal androgens determine the development of gender identity. Fifteen girls with CAH (range of genital Prader stage, 2–4/5), 30 control girls, and 16 control boys (age range, 5–12 years) underwent 2 gender-play observation sessions, and a gender identity interview yielding scales of gender confusion/dysphoria. About half a year earlier, mothers had completed 2 questionnaires concerning their childrens gender-related behavior. The results showed that, as expected, CAH girls scored more masculine than control girls on all scales measuring gender-related behavior, with robust effect sizes. By contrast, neither conventionally significant differences nor trends were found on the 3 scales of the gender identity interview. We conclude that prenatal androgenization of 46,XX fetuses leads to marked masculinization of later gender-related behavior, but the absence of any increased gender-identity confusion/dysphoria does not indicate a direct determination of gender identity by prenatal androgens and does not, therefore, support a male gender assignment at birth of the most markedly masculinized girls.

Serologic Detection of a Y-Linked Gene in XX Males and XX True Hermaphrodites

To test the hypothesis that H-Y antigen (present on both somatic and germ cells in normal males but not normal females) is essential for testicular differentiation, we studied four XX males and three XX true hermaphrodites. Blood cells from six subjects and cultured gonadal fibroblasts from a seventh expressed H-Y antigen. Since expression of this antigen requires the presence of a gene normally carried by the Y chromosome, this gene, and perhaps additional Y chromosomal material, should have been present in the genome of these subjects. In one patient this presence is accounted for by a Y-to-X translocation, detectable by chromosome banding. In another a normal Y chromosome was present in a minor population of cells. In the remaining five, no karyotypic abnormality was detectable. Immunologic detection of H-Y antigen is a sensitive test for the presence of the Y chromosome or of its male-determining segment.

Steroid 11β- hydroxylase deficiency congenital adrenal hyperplasia

Congenital adrenal hyperplasia due to steroid 11beta-hydroxylase deficiency is a genetic disorder of steroidogenesis, transmitted as an autosomal recessive trait. It is associated with low renin hypertension, hypokalemia, hyperandrogenemia and genital ambiguity in affected females. Mutations in the CYP11B1 gene, causing 11beta-hydroxylase deficiency in the zona fasciculata in the adrenal cortex, have been identified. The indicators of congenital adrenal hyperplasia caused by 11beta-hydroxylase deficiency, include increased serum concentrations of desoxycorticosterone, 11 deoxycortisol and delta4-androstenedione, and suppressed plasma renin concentrations. The disorder is treated by administration of glucocorticoids.

Noninvasive Prenatal Diagnosis of Congenital Adrenal Hyperplasia Using Cell-Free Fetal DNA in Maternal Plasma

CONTEXT Congenital adrenal hyperplasia (CAH) is an autosomal recessive condition that arises from mutations in CYP21A2 gene, which encodes for the steroidogenic enzyme 21-hydroxylase. To prevent genital ambiguity in affected female fetuses, prenatal treatment with dexamethasone must begin on or before gestational week 9. Currently used chorionic villus sampling and amniocentesis provide genetic results at approximately 14 weeks of gestation at the earliest. This means that mothers who want to undergo prenatal dexamethasone treatment will be unnecessarily treating seven of eight fetuses (males and three of four unaffected females), emphasizing the desirability of earlier genetic diagnosis in utero. OBJECTIVE The objective of the study was to develop a noninvasive method for early prenatal diagnosis of fetuses at risk for CAH. PATIENTS Fourteen families, each with a proband affected by phenotypically classical CAH, were recruited. DESIGN Cell-free fetal DNA was obtained from 3.6 mL of maternal plasma. Using hybridization probes designed to capture a 6-Mb region flanking CYP21A2, targeted massively parallel sequencing (MPS) was performed to analyze genomic DNA samples from parents and proband to determine parental haplotypes. Plasma DNA from pregnant mothers also underwent targeted MPS to deduce fetal inheritance of parental haplotypes. RESULTS In all 14 families, the fetal CAH status was correctly deduced by targeted MPS of DNA in maternal plasma, as early as 5 weeks 6 days of gestation. CONCLUSIONS MPS on 3.6 mL plasma from pregnant mothers could potentially provide the diagnosis of CAH, noninvasively, before the ninth week of gestation. Only affected female fetuses will thus be treated. Our strategy represents a generic approach for noninvasive prenatal testing for an array of autosomal recessive disorders.