Elaine Maria Frade Costa

TAC3/TACR3 Mutations Reveal Preferential Activation of Gonadotropin-Releasing Hormone Release by Neurokinin B in Neonatal Life Followed by Reversal in Adulthood

CONTEXT Mutations in TAC3 and TACR3 (encoding neurokinin B and its receptor) have been identified in Turkish patients with idiopathic hypogonadotropic hypogonadism (IHH), but broader populations have not yet been tested and genotype-phenotype correlations have not been established. OBJECTIVE A broad cohort of normosmic IHH probands was screened for mutations in TAC3/TACR3 to evaluate the prevalence of such mutations and define the genotype/phenotype relationships. DESIGN AND SETTING The study consisted of sequencing of TAC3/TACR3, in vitro functional assays, and neuroendocrine phenotyping conducted in tertiary care centers worldwide. PATIENTS OR OTHER PARTICIPANTS 345 probands, 18 family members, and 292 controls were studied. INTERVENTION Reproductive phenotypes throughout reproductive life and before and after therapy were examined. MAIN OUTCOME MEASURE Rare sequence variants in TAC3/TACR3 were detected. RESULTS In TACR3, 19 probands harbored 13 distinct coding sequence rare nucleotide variants [three nonsense mutations, six nonsynonymous, four synonymous (one predicted to affect splicing)]. In TAC3, one homozygous single base pair deletion was identified, resulting in complete loss of the neurokinin B decapeptide. Phenotypic information was available on 16 males and seven females with coding sequence variants in TACR3/TAC3. Of the 16 males, 15 had microphallus; none of the females had spontaneous thelarche. Seven of the 16 males and five of the seven females were assessed after discontinuation of therapy; six of the seven males and four of the five females demonstrated evidence for reversibility of their hypogonadotropism. CONCLUSIONS Mutations in the neurokinin B pathway are relatively common as causes of hypogonadism. Although the neurokinin B pathway appears essential during early sexual development, its importance in sustaining the integrity of the hypothalamic-pituitary-gonadal axis appears attenuated over time.

Male pseudohermaphroditism due to steroid 5α-reductase 2 deficiency. Diagnosis, psychological evaluation, and management

Sixteen subjects (from 10 Brazilian families) with male pseudohermaphroditism due to steroid 5alpha-reductase 2 deficiency have been evaluated in 1 clinic. The diagnoses were made on the basis of normal plasma testosterone values, normal or low plasma dihydrotestosterone levels and high testosterone/dihydrotestosterone ratios in the basal state in postpubertal subjects or after treatment with either human chorionic gonadotropin or testosterone in prepubertal subjects. The analysis of the ratios of etiocholanolone to androsterone in urine confirmed the diagnosis in all subjects who were tested, and the molecular basis of the underlying mutations was established in 9 of the families. Fourteen of the individuals were evaluated by the same psychologist. All subjects but 1 were given a female sex assignment at birth. Three of the subjects (1 the sibling of an individual who has undergone female to male social behavior) maintain a female social sex; they have been gonadectomized and treated with exogenous estrogens. Ten of 13 subjects of postpubertal age underwent a change of social sex from female to male, had surgical correction of the hypospadias, and were treated with high-dose testosterone esters by parenteral injection and subsequently with dihydrotestosterone cream. These regimens brought serum dihydrotestosterone levels to the normal male range (or above) but resulted only in limited growth of the prostate and penis and, in some, increase in body and facial hair and enhancement of libido and sexual performance. Treatment of the prepubertal boys with testosterone and/or dihydrotestosterone resulted in a doubling of penis size.

Loss-of-Function Mutations in the Genes Encoding Prokineticin-2 or Prokineticin Receptor-2 Cause Autosomal Recessive Kallmann Syndrome

CONTEXT Physiological activation of the prokineticin pathway has a critical role in olfactory bulb morphogenesis and GnRH secretion in mice. OBJECTIVE To investigate PROK2 and PROKR2 mutations in patients with hypogonadotropic hypogonadism (HH) associated or not with olfactory abnormalities. DESIGN We studied 107 Brazilian patients with HH (63 with Kallmann syndrome and 44 with normosmic HH) and 100 control individuals. The coding regions of PROK2 and PROKR2 were amplified by PCR followed by direct automatic sequencing. RESULTS In PROK2, two known frameshift mutations were identified. Two brothers with Kallmann syndrome harbored the homozygous p.G100fsX121 mutation, whereas one male with normosmic HH harbored the heterozygous p.I55fsX56 mutation. In PROKR2, four distinct mutations (p.R80C, p.Y140X, p.L173R, and p.R268C) were identified in five patients with Kallmann syndrome and in one patient with normosmic HH. These mutations were not found in the control group. The p.R80C, p.L173R, and p.R268C missense mutations were identified in the heterozygous state in the HH patients and in their asymptomatic first-degree relatives. In addition, no mutations of FGFR1, KAL1, GnRHR, KiSS-1, or GPR54 were identified in these patients. Notably, the new nonsense mutation (p.Y140X) was identified in the homozygous state in an anosmic boy with micropenis, bilateral cryptorchidism, and high-arched palate. His asymptomatic parents were heterozygous for this severe defect. CONCLUSION We expanded the repertoire of PROK2 and PROKR2 mutations in patients with HH. In addition, we show that PROKR2 haploinsufficiency is not sufficient to cause Kallmann syndrome or normosmic HH, whereas homozygous loss-of-function mutations either in PROKR2 or PROK2 are sufficient to cause disease phenotype, in accordance with the Prokr2 and Prok2 knockout mouse models.

Male pseudohermaphroditism due to 17 beta-hydroxysteroid dehydrogenase 3 deficiency. Diagnosis, psychological evaluation, and management.

Ten male pseudohermaphrodites with 17 beta-hydroxysteroid dehydrogenase 3 (17 beta-HSD3) deficiency were evaluated in 1 clinic with an average follow-up of 10.1 years. The diagnoses were made by demonstrating low to normal serum testosterone levels, high androstenedione levels, and high ratios of serum androstenedione to testosterone in the basal state or after treatment with human chorionic gonadotropin. The molecular features of the underlying mutations were identified in all 7 families. Two additional males in the same families are believed to be affected on the basis of history obtained from family members. All of the 46,XY individuals in these families were registered at birth and raised as females (despite the presence of ambiguous genitalia in all or most), and all virilized after the time of expected puberty due to a rise in serum testosterone to or toward the normal male range. The age at diagnosis varied from 4 to 37 years. Ten individuals were studied by the same psychologist, and change of gender role (social sex) from female to male occurred in 3 subjects and in the 2 presumed affected subjects not studied. The individual with the highest serum testosterone level maintained female sexual identity, and in 2 families some of the affected males changed gender role and others did not. Thus, while androgen action plays a role in the process, additional undefined psychological, social, and/or biologic factors must be determinants of gender identity/role behavior. Management of the 7 individuals who chose to maintain female sex roles included castration, clitoroplasty, vaginal enlargement procedures when appropriate, treatment of hirsutism, cricoid cartilage reduction, and estrogen replacement. Three of the 7 are married (2 twice), 1 is involved in a long-term heterosexual relationship, 1 is engaged to be married, and the other 2 are not married and not believed to be sexually active. The 3 subjects who changed gender role behavior to male underwent hypospadias repair, and 1 was given supplemental testosterone therapy. One of these men is divorced, and the other 2 (aged 29 and 35 years) are unmarried. The diagnosis in 8 of these subjects was made after the time of expected puberty; it is unclear whether the functional and social outcomes would have been different if the diagnosis had been made and therapy begun earlier in life.

46,XY disorders of sex development (DSD)

The term disorders of sex development (DSD) includes congenital conditions in which development of chromosomal, gonadal or anatomical sex is atypical.

Height and bone mineral density in androgen insensitivity syndrome with mutations in the androgen receptor gene

Introduction and hypothesisAndrogen insensitivity syndrome (AIS) constitutes a natural model to study effects of androgens and estrogens on growth and bone density. We evaluated height and bone density in patients with AIS with mutations in the androgen receptor (AR) gene.MethodsA retrospective analysis was conducted of eight subjects with complete AIS (CAIS) and four with partial AIS (PAIS) submitted to gonadectomy followed by estrogen replacement, and three with PAIS who did not undergo gonadectomy. Standing height and bone mineral apparent density (BMAD) by DXA were measured and compared with male (zm) and female (zf) reference populations. The z-scores were compared with a value of zero using the one-sample t-test.ResultsFinal heights of patients with CAIS and PAIS were intermediate between those predicted for females and males. BMAD of the lumbar spine in CAIS and PAIS after gonadectomy and estrogen replacement (zf = − 1.56 ± 1.04, P = 0.006, and zm = − 0.75 ± 0.89, P = 0.04) indicated vertebral bone deficit, whereas BMAD at the femoral neck was normal. No patient reported fractures.ConclusionSubjects with AIS had mean final height intermediate between mean normal male and female, and decreased bone mineral density in the lumbar spine. These data suggest an important role for androgens in normal male growth and bone density not replaced by estrogens.

Nonsense mutations in FGF8 gene causing different degrees of human gonadotropin-releasing deficiency.

CONTEXT FGFR1 mutations cause isolated hypogonadotropic hypogonadism (IHH) with or without olfactory abnormalities, Kallmann syndrome, and normosmic IHH respectively. Recently, missense mutations in FGF8, a key ligand for fibroblast growth factor receptor (FGFR) 1 in the ontogenesis of GnRH, were identified in IHH patients, thus establishing FGF8 as a novel locus for human GnRH deficiency. OBJECTIVE Our objective was to analyze the clinical, hormonal, and molecular findings of two familial IHH patients due to FGF8 gene mutations. METHODS AND PATIENTS The entire coding region of the FGF8 gene was amplified and sequenced in two well-phenotyped IHH probands and their relatives. RESULTS Two unique heterozygous nonsense mutations in FGF8 (p.R127X and p.R129X) were identified in two unrelated IHH probands, which were absent in 150 control individuals. These two mutations, mapped to the core domain of FGF8, impact all four human FGF8 isoforms, and lead to the deletion of a large portion of the protein, generating nonfunctional FGF8 ligands. The p.R127X mutation was identified in an 18-yr-old Kallmann syndrome female. Her four affected siblings with normosmic IHH or delayed puberty also carried the p.R127X mutation. Additional developmental anomalies, including cleft lip and palate and neurosensorial deafness, were also present in this family. The p.R129X mutation was identified in a 30-yr-old man with familial normosmic IHH and severe GnRH deficiency. CONCLUSIONS We identified the first nonsense mutations in the FGF8 gene in familial IHH with variable degrees of GnRH deficiency and olfactory phenotypes, confirming that loss-of-function mutations in FGF8 cause human GnRH deficiency.

Management of ambiguous genitalia in pseudohermaphrodites: new perspectives on vaginal dilation.

OBJECTIVE To evaluate vaginal size and sexual activity after different techniques of feminization of external genitalia in patients with pseudohermaphroditism. DESIGN Retrospective clinical study. SETTING Pseudohermaphrodite patients seen at our institution. PATIENT(S) Three female and 20 male pseudohermaphrodites raised as females. INTERVENTION(S) Bilateral orchidectomy, feminization of external genitalia (clitoridectomy or clitoroplasty, urogenital sinus enlargement), and/or neovaginoplasty or vaginal dilation with acrylic molds. MAIN OUTCOME MEASURE(S) Psychological evaluation, vaginal size, and quality of intercourse. RESULT(S) All patients referred sexual drive to men. Fifty percent of the patients who were submitted to neovaginoplasty referred pain or bleeding during sexual intercourse. On the other hand, 87% of the patients who were submitted to vaginal dilation with acrylic molds, after genitoplasty or not, referred satisfactory sexual intercourse. All patients who were submitted to clitoroplasty referred orgasm and 29% of the patients submitted to clitoridectomy referred no orgasm. Of three patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency, two became pregnant and delivered normal children through cesarian section. CONCLUSION(S) In pseudohermaphrodites with female social sex, surgical correction of external genitalia performed in childhood and vaginal dilation with acrylic molds performed when they wished to start having sexual intercourse resulted in best outcome.

Effects of endocrine disruptors in the development of the female reproductive tract

Environmental agencies have identified a growing number of environmental contaminants that have endocrine disrupting activity, and these can become a major public health problem. It is suggested that endocrine disruptors could account for the higher-than-expected increase in the prevalence of some non-communicable diseases, such as obesity, diabetes, thyroid diseases, and some cancers. Several endocrine Disrupting Chemicals (EDCs), such as pesticides, bisphenol A, phthalates, dioxins, and phytoestrogens, can interact with the female reproductive system and lead to endocrine disruption. Initially, it was assumed that EDCs exert their effects by binding to hormone receptors and transcription factors, but it is currently known that they may also alter the expression of enzymes involved in the synthesis or catabolism of steroids. Biomonitoring studies have identified these compounds in adults, children, pregnant women, and fetuses. Among the diseases of the female reproductive tract associated with EDCs exposure are the following: precocious puberty, polycystic ovary syndrome, and premature ovarian failure. The different populations of the world are exposed to a great number of chemicals through different routes of infection; despite the various available studies, there is still much doubt regarding the additive effect of a mixture of EDCs with similar mechanisms of action.

Long-Term Surgical Outcome of Masculinizing Genitoplasty in Large Cohort of Patients With Disorders of Sex Development

PURPOSE We evaluated the results of masculinizing genitoplasty in a large cohort of patients with disorders of sex development treated at a single public tertiary center. MATERIALS AND METHODS We evaluated 52 patients with 46,XY and 7 with 46,XX disorders of sex development with proximal hypospadias and genital ambiguity reared as males who had undergone surgery between 1965 and 2008. Mean +/- SD followup was 14.1 +/- 9.2 years and median age at last examination was 22 years, with 38 patients having reached adulthood. Morphological result and urinary stream were evaluated by a physician. Urinary and sexual symptoms, and satisfaction with surgical results were assessed by questionnaire. RESULTS Mean penile length at diagnosis was compared between 46,XY patients and showed that those with 5alpha-reductase 2 deficiency had the shortest penile length (-5.4 +/- 1.2 SD). At the last clinical evaluation following surgical and hormonal treatment mean +/- SD penile length in 38 adults was 7.5 +/- 2.1 cm (range 4 to 12), corresponding to -4.3 +/- 1.3 SD (-6.5 to -1.5). All but 2 patients had penile length less than -2 SD. At that time mean penile length remained shorter in patients with 5alpha-reductase 2 deficiency (-5.4 +/- 1 SD) compared to those with testosterone production deficiency or indeterminate disorders of sex development (p <0.05). There was no statistical difference between mean penile length before and after treatment in all etiological groups (p >0.05). Morphological results were good in 43% of patients, fair in 54% and poor in 3%. The most common complications were urethral fistula (51%) and urethral stenosis (22%). Dribbling after voiding was the most frequent urinary symptom. Satisfaction with surgical results was reported by 89% of patients. Among adults 87% were sexually active, with 64% reporting normal sexual activity. CONCLUSIONS Most patients with 46,XY disorders of sex development were satisfied with long-term results of masculinizing genitoplasty, although specific complaints about small penile length, sexual activity and urinary symptoms were frequent. New surgical approaches should be developed to ensure full satisfaction in adulthood among patients with disorders of sex development.