Charles Sultan

Phenotypical, Biological, and Molecular Heterogeneity of 5α-Reductase Deficiency: An Extensive International Experience of 55 Patients

CONTEXT In 46,XY disorders of sex development, 5α-reductase deficiency is rare and is not usually the first-intention diagnosis in newborn ambiguous genitalia, contrary to partial androgen insensitivity syndrome. Yet the cause of ambiguous genitalia may guide sex assignment, and rapid, precise diagnosis of 5α-reductase deficiency is essential. OBJECTIVE The aim of the study was to describe relevant data for clinical diagnosis, biological investigation, and molecular determination from 55 patients with srd5A2 mutations identified in our laboratory over 20 yr to improve early diagnosis. SETTING The study was performed at Montpellier University Hospital. PATIENTS We studied a cohort of 55 patients with srd5A2 gene mutations. MAIN OUTCOME MEASURE(S) Genetic analysis of srd5A2 was conducted. RESULTS Clitoromegaly (49.1%) and microphallus with various degrees of hypospadias (32.7%) were frequent phenotypes. Female external genitalia (7.3%) and isolated micropenis (3.6%) were rare. Seventy-two percent of patients were initially assigned to female gender; five of them (12.5%) switched to male sex in peripuberty. Over 72% of patients were considered for 5α-reductase deficiency diagnosis when the testosterone/dihydrotestosterone cutoff was 10. In 55 patients (with 20 having a history of consanguinity), we identified 33 different mutations. Five have never been reported: p.G32S, p.Y91H, p.G104E, p.F223S, and c.461delT. Homozygous mutations were present in 69.1% of cases, compound heterozygous mutations in 25.5%, and compound heterozygous mutations alone with the V89L polymorphism in 5.4%. Exons 1 and 4 were most affected, with 35.8 and 21.7% mutant alleles per exon, respectively. CONCLUSIONS In the largest cohort to date, we demonstrate a wide spectrum of phenotypes and biological profiles in patients with 5α-reductase deficiency, whatever their geographical or ethnic origins.

Prevalence of hypospadias in grandsons of women exposed to diethylstilbestrol during pregnancy: a multigenerational national cohort study

Prenatal diethylstilbestrol (DES)-exposed mice have raised the suspicion of a transgenerational effect in the occurrence of genital malformation in males. This nationwide cohort study in collaboration with a French association of DES-exposed women studied 529 families and showed that a significant proportion of boys born to DES daughters exhibited hypospadias with no other molecular defects identified.

Prenatal environmental risk factors for genital malformations in a population of 1442 French male newborns: a nested case–control study

BACKGROUND Over the past decades, an increasing trend in male external genital malformations such as cryptorchidism and hypospadias has led to the suspicion that environmental chemicals are detrimental to male fetal sexual development. Several environmental pollutants, including organochlorine pesticides, polychlorinated biphenyls, bisphenol A, phthalates, dioxins and furans have estrogenic and anti-androgenic activity and are thus considered as endocrine-disrupting chemicals (EDCs). Since male sex differentiation is critically dependent on the normal production and action of androgens during fetal life, EDCs may be able to alter normal male sex differentiation. OBJECTIVE The objective of this study was to determine the incidence of external genital malformations in a population of full-term newborn males in southern France. We also performed a case-control study to identify the risk factors for male external genital malformations, with a focus on parental occupational exposure to EDCs. METHODS Over a 16-month period, 1615 full-term newborn males with a birth weight above 2500 g were registered on a level-1 maternity ward, and the same pediatrician systematically examined 1442 of them (89%) for cryptorchidism, hypospadias and micropenis. For every male newborn with genital malformation, we enrolled nearly two males matched for age, parity and term. All parents of the case and control newborns were interviewed about pregnancy aspects, personal characteristics, lifestyle and their occupational exposure to EDCs using a detailed questionnaire. RESULTS We report 39 cases of genital malformation (2.70%), with 18 cases of cryptorchidism (1.25%), 14 of hypospadias (0.97%), 5 of micropenis (0.35%) and 2 of 46,XY disorders of sexual differentiation (DSD; 0.14%). We observed a significant relationship between newborn cryptorchidism, hypospadias or micropenis and parental occupational exposure to pesticides [odds ratio (OR) = 4.41; 95% confidence interval (95% CI), 1.21-16.00]. Familial clustering for male external genital malformations (OR = 7.25; 95% CI, 0.70-74.30) and medications taken by mothers during pregnancy (OR = 5.87; 95% CI, 0.93-37.00) were associated with the risk of cryptorchidism, hypospadias and micropenis, although the association was not statistically significant. CONCLUSIONS Although the causes of male genital malformation are multifactorial, our data support the hypothesis that prenatal contamination by pesticides may be a potential risk factor for newborn male external genital malformation and it should thus be routinely investigated in all undervirilized newborn males.

Androgens and fetal growth

Boys are heavier than girls at term birth. Children with a 46,XY karyotype and androgen insensitivity syndrome (clinically complete form and/or proven mutations in the androgen receptor gene) were found to have a birth weight comparable to that of girls. These findings support the hypothesis that the difference in birth weight between boys and girls is generated by androgen action.

The clinical and molecular heterogeneity of 17βHSD-3 enzyme deficiency.

17-β-hydroxysteroid dehydrogenase type 3 (17βHSD-3) deficiency is a rare, but frequently misdiagnosed autosomal recessive cause of 46,XY disorder of sex development (DSD). 17βHSD-3 enzyme is present almost exclusively in the testes and converts Δ4-androstenedione (Δ4) to testosterone (T). The diagnosis can be easily missed in early childhood as the clinical presentation may be subtle. Any young girl with an inguinal hernia, mild clitoromegaly, single urethral opening or urogenital sinus should raise suspicion. If not diagnosed early, patients present with severe virilization and primary amenorrhea in adolescence and may undergo a change from a female to male gender role. A low T/Δ4 ratio on baseline or hCG (human chorionic gonadotropin)-stimulated testing is suggestive of 17βHSD-3 deficiency. The diagnosis can be confirmed with molecular genetic studies. This review summarizes the clinical presentations, reported mutations, diagnosis, treatment and clinical course of this disorder. The Arg80 site in exon 3 is the most common location of repeated mutations and can be considered a hot spot in certain Arab populations.

Testosterone Is Significantly Reduced in Endurance Athletes without Impact on Bone Mineral Density

Aims: To compare the basal plasma reproductive hormonal profile in three groups of athletes involved in different training programs, and to define the relationship between androgen level and bone mineral density (BMD) in male athletes. Methods: Basal serum total testosterone (TT), free androgen index (FAI), sex hormone-binding globulin (SHBG), cortisol, cortisol to TT ratio, luteinizing hormone (LH), estrogen and BMD were evaluated in cyclists (CY; n = 11), triathletes (TR; n = 14) and swimmers (SW; n = 13) and compared with less active controls (n = 10). Results: TT and FAI levels were lower (p < 0.05) in CY and TR, whereas the ratio of cortisol to TT was increased in CY only (p < 0.05). No alteration in serum LH, SHBG, estrogen or cortisol concentration was observed. BMD was higher in the proximal femur in TR (p < 0.05). No BMD or hormonal differences were found in SW. Conclusion: Only the endurance training of CY and TR induced androgen deficiency without apparent alteration of BMD.

Steroidogenic factor-1 (SF-1) gene mutation as a frequent cause of primary amenorrhea in 46,XY female adolescents with low testosterone concentration

BackgroundPrimary amenorrhea due to 46,XY disorders of sex differentiation (DSD) is a frequent reason for consultation in endocrine and gynecology clinics. Among the genetic causes of low-testosterone primary amenorrhea due to 46,XY DSD, SRY gene is reported to be frequently involved, but other genes, such as SF1 and WT1, have never been studied for their prevalence.MethodsWe directly sequenced SRY, SF1 and WT1 genes in 15 adolescent girls with primary amenorrhea, low testosterone concentration, and XY karyotype, to determine the prevalence of mutations. We also analyzed the LH receptor gene in patients with high LH and normal FSH concentrations.ResultsAmong the 15 adolescents with primary amenorrhea and low testosterone concentration, we identified two new SRY mutations, five new SF1 mutations and one new LH receptor gene mutation. Our study confirms the 10-15% prevalence of SRY mutations and shows the high prevalence (33%) of SF1 abnormalities in primary amenorrhea due to 46,XY DSD with low plasma testosterone concentration.ConclusionsThe genetic analysis of low-testosterone primary amenorrhea is complex as several factors may be involved. This work underlines the need to systematically analyze the SF1 sequence in girls with primary amenorrhea due to 46,XY DSD and low testosterone, as well as in newborns with 46,XY DSD.

Appendicular skeletal muscle mass is the strongest independent factor associated with femoral neck bone mineral density in adult and older men.

The relationship between bone mass and muscle mass may be due to the site-specific effects of loading on bone in adults and to lifestyle, nutritional, and hormonal factors. Another hypothesis is that the maintenance with aging of both appendicular muscle and bone mass may be determined by factors independent of all these previous factors, including genetic factors. In 160 healthy men aged 20 to 72years, we recorded femoral neck bone mineral density (FN BMD), relative appendicular skeletal muscle mass [RASM; appendicular skeletal muscle mass (kg)/height (cm)], age, body mass, maximum grip and knee extension strength, lifetime physical activities, calcium intake, tobacco smoking, and serum parathyroid hormone (PTH), estradiol (E2), free testosterone, dehydroepiandrosterone sulphate (DHEAS), insulin-like growth factor (IGF-I), sex hormone-binding globulin (SHBG), calcium, 25(OH) vitamin D, albumin, and creatinine clearance. The correlation between FN BMD and RASM (that includes upper and lower limb muscle mass) was of slightly greater magnitude than that between FN BMD and the relative upper limb muscle mass and between FN BMD and the relative leg muscle mass (r=0.39; p< or =0.001 versus r=0.36; p< or =0.001 and r=0.34; p< or =0.001, respectively). The stepwise multiple linear regression model showed that FN BMD was significantly associated with RASM (15% of FN BMD variance, p<0.0001), age (10% of FN BMD variance, p<0.0001), physical activities from age 11-20years (5% of FN BMD variance, p<0.01), and blood PTH, IGF-I, and creatinine clearance, (2%, 2%, and 1% of FN BMD variance, respectively, p<0.05). These results show that RASM, with ASM measured by DXA, is the strongest factor associated with FN BMD in men. It remains to be determined whether assessing RASM by anthropometric methods would help screening adult men at risk of low FN BMD. Furthermore, since RASM is associated with FN BMD independently of appendicular skeletal loads and other lifestyle, nutritional, and hormonal factors, this suggests that common factors, possibly genetic factors, might also influence the coupled maintenance of appendicular muscle mass and FN BMD in adult men.

Is Hypospadias Associated with Prenatal Exposure to Endocrine Disruptors? A French Collaborative Controlled Study of a Cohort of 300 Consecutive Children Without Genetic Defect

BACKGROUND Numerous studies have focused on the association between endocrine-disrupting chemicals (EDCs) and hypospadias. Phenotype variability, the absence of representative comparison groups and concomitant genetic testing prevent any definitive conclusions. OBJECTIVE To identify the role of occupational and environmental exposures to EDCs in nongenetic isolated hypospadias. DESIGN, SETTING, AND PARTICIPANTS A total of 408 consecutive children with isolated hypospadias and 302 normal boys were prospectively included (2009-2014) in a multi-institutional study in the south of France, the area of the country with the highest prevalence of hypospadias surgery. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS In patients without AR, SRD5A2, and MAMLD1 mutations, parental occupational and professional exposures to EDCs were evaluated based on European questionnaire QLK4-1999-01422 and a validated job-exposure matrix for EDCs. Environmental exposure was estimated using the zip code, the type of surrounding hazards, and distance from these hazards. Multivariate analysis was performed. RESULTS Fetal exposure to EDCs around the window of genital differentiation was more frequent in the case of hypospadias (40.00% vs 17.55%, odds ratio 3.13, 95% confidence interval 2.11-4.65). The substances were paints/solvents/adhesives (16.0%), detergents (11.0%), pesticides (9.0%), cosmetics (5.6%), and industrial chemicals (4.0%). Jobs with exposure were more frequent in mothers of hypospadiac boys (19.73% vs 10.26%, p=0.0019), especially cleaners, hairdressers, beauticians, and laboratory workers. Paternal job exposure was more frequent in the cases of hypospadias (40.13% vs 27.48%, p=0.02). Industrial areas, incinerators, and waste areas were more frequent within a 3-km radius for mothers of hypospadiac boys (13.29% vs. 6.64%, p<0.00005). Association of occupational and environmental exposures increases this risk. CONCLUSIONS This multicenter prospective controlled study with a homogeneous cohort of hypospadiac boys without genetic defects strongly suggests that EDCs are a risk factor for hypospadias through occupational and environmental exposure during fetal life. The association of various types of exposures may increase this risk. PATIENT SUMMARY Our multi-institutional study showed that parental professional, occupational, and environmental exposures to chemical products increase the risk of hypospadias in children.

High prevalence of micropenis in 2710 male newborns from an intensive‐use pesticide area of Northeastern Brazil

Exposure to endocrine-disrupting chemicals (EDCs) has been suggested to contribute to the increasing trends of external genital malformation in male newborns. In Northeastern Brazil, the poor sanitary conditions found in the favelas encourage the widespread use of pesticides. This 2-year study of a total birth cohort of full-term male newborns in the regional hospitals of Campina Grande (Paraíba, Brazil) sought to (1) accurately establish for the first time the incidences of neonatal male genital malformations, (2) investigate the endocrine and genetic aetiologies of these malformations, and (3) evaluate their associations with possible prenatal exposure to EDCs. A total of 2710 male newborns were explored for cryptorchidism, hypospadias and micropenis. Cases were referred to the Pediatric Endocrine Clinic for endocrine and genetic investigations, and all parents were interviewed about their environmental/occupational exposure to EDCs before/during pregnancy by paediatric endocrinologists using a detailed questionnaire. We observed 56 cases of genital malformation (2.07%), including 23 cryptorchidism (0.85%), 15 hypospadias (0.55%), and 18 micropenis (0.66%). All cases exhibited normal/subnormal testosterone production and none presented androgen receptor or 5α-reductase gene mutation. More than 92% of these newborns presented foetal contamination by EDCs, as their mothers reported daily domestic use of pesticides (i.e., DDT) and other EDCs. Most of these undervirilized male newborns presented additional EDC contamination, as 80.36% of the mothers and 58.63% of the fathers reported paid or unpaid work that entailed the use of pesticides and other EDCs before/during pregnancy for the mothers and around the time of fertilization for the fathers. The high rate of micropenis in our population associated with an elevated percentage of parental environmental/occupational exposure to EDCs before/during pregnancy indicates that foetal contamination may be a risk factor for the development of male external genital malformation.