17ß hydroxysteroid dehydrogenase 3 deficiency in 46,XY disorders of sex development: Our experience and a gender role-focused systematic review.

OBJECTIVES: To describe Asian Indian patients with 17ß hydroxysteroid dehydrogenase 3 (17ßHSD3) deficiency and to perform a systematic review to determine the factors influencing gender role in 46,XY disorder of sex development (DSD) due to 17ßHSD3 deficiency. PATIENTS AND DESIGN: We present the phenotypic and genotypic data of 10 patients (9 probands and 1 affected family member) with 17ßHSD3 deficiency from our 46,XY DSD cohort (N = 150; Western India) and a systematic review of 152 probands with genetically proven, index 17ßHSD3 deficiency patients from the world literature to identify the determinants of gender role. RESULTS: 17ßHSD3 deficiency was the third most common (6%) cause of non-dysgenetic 46,XY DSD in our cohort. Five patients each had prepubertal (atypical genitalia) and pubertal (primary amenorrhoea) presentations. Six patients were initially reared as female of whom two (one each in prepubertal and pubertal age) changed their gender role. Ten pathogenic molecular variants (six novel) were observed. In the systematic review, initial male sex of rearing was uncommon (10.5%) and was associated with atypical genitalia, higher testosterone/androstenedione (T/A) ratio and Asian origin. Gender role change to male was seen in 10.3% of patients with initial female sex of rearing and was associated with Asian origin but unrelated to pubertal androgens or molecular variant severity. It has not been reported in patients of European origin. CONCLUSIONS: We report the first Indian case series of 17ßHSD3 deficiency, the third most common cause of 46,XY DSD, with six novel molecular variants. Distinct geographical differences in the frequency of initial male sex of rearing and gender role change to male in those initially reared as females in 17ßHSD3 deficiency were noted which needs further evaluation for the underlying molecular mechanisms.

17ß-hydroxysteroid dehydrogenase type 3 deficiency: female sex assignment and follow-up.

BACKGROUND: Deficiency of 17ß-hydroxysteroid dehydrogenase type 3 (17ß-HSD3) is a rare autosomal recessive 46,XY disorder of sex development (DSD). It is due to pathogenetic variants in the HSD17B3 gene. Mutated genes encode an abnormal enzyme with absent or reduced ability to convert Δ4-androstenedione (Δ4-A) to testosterone (T) in the fetal testis. Affected individuals are usually raised as females and diagnosis is made at puberty, when they show virilization. METHODS: A girl with a presumptive diagnosis of complete androgen insensitivity syndrome underwent endocrine and genetic assessment. Long-term follow-up was reported. RESULTS: The diagnosis of 17ß-HSD3 deficiency was made (stimulated T/Δ4-A ratio: 0.15; HSD17B3 gene analysis: c.277+4A>T in intron 3/c.640_645del (p.Glu214_Glu215del) in exon 9. After extensive information, parents decided to maintain female sex. Gonadal removal was performed and histological evaluation demonstrated deep fibrosis of testicular tissue. Follow-up till 8.5 years of age showed somatic and neuro-psychological development fitting with the female sex. CONCLUSIONS: Management of a child with the rare 17ß-HSD3 deficiency remains challenging. Any decision must be carefully evaluated with parents. Long-term follow-up must be warranted by a multidisciplinary DSD team to evaluate the adequacy of the choices made on quality of life in later life.

A novel nonsense mutation in HSD17B3 gene in a Tunisian patient with sexual ambiguity.

INTRODUCTION: 17ß-hydroxysteroid dehydrogenase type 3 (HSD17B3) isoenzyme is present almost exclusively in the testes and converts delta 4 androstenedione to testosterone. Mutations in the HSD17B3 gene cause HSD17B3 deficiency and result in 46,XY Disorders of Sex Development (46,XY DSD). AIM: This study aimed to present the clinical and biochemical features of a Tunisian patient who presented a sexual ambiguity orienting to HSD17B3 deficiency and to search for a mutation in the HSD17B3 gene by DNA sequencing. METHODS: Polymerase chain reaction (PCR) amplification and subsequent sequencing of all the coding exons of HSD17B3 gene were performed on genomic DNA from the patient, her family, and 50 controls. RESULTS: Genetic mutation analysis of the HSD17B3 gene revealed the presence of a novel homozygous nonsense mutation in the exon 9 (c.618 C>A) leading to the substitution p.C206X. The mutation p.C206X in the coding exons supports the hypothesis of HSD17B3 deficiency in our patient. CONCLUSION: The patient described in this study represented a new case of a rare form of 46,XY DSD, associated to a novel gene mutation of HSD17B3 gene. The screening of this mutation is useful for confirming the diagnosis of HSD17B3 deficiency and for prenatal diagnosis.

46,XY Sex Development Defect due to a Novel Homozygous (Splice Site) c.673_1G>C Variation in the HSD17B3 Gene: Case Report

The enzyme 17-ß-hydroxysteroid dehydrogenase type 3 (17ß-HSD3) catalyzes the biosynthesis of testosterone (T) from Δ4-androstenedione, and plays an important role in the final steps of androgen synthesis. 17ß-HSD3 deficiency originates from mutations in the HSD17B gene, causing an autosomal recessive 46,XY sex developmental disorder (DSD). Patients with 46,XY karyotype can exhibit a wide phenotypic spectrum, varying from complete external female genitalia to male genitalia with hypospadias. Here we report a case of 17ß-HSD3 deficiency diagnosed in the infantile period who was later found to have a novel HSD17B3 gene variation. The 14-month old patient, who exhibited a female phenotype, presented with a bilateral lump in the inguinal area. Imaging revealed bilateral testicular gonads in the inguinal area. Hormonal evaluation showed low levels of basal and stimulated serum T, a high level of androstenedione (A), and a low T/A ratio. Chromosomal analysis showed 46,XY karyotype. Sequence analysis of the HSD17B3 gene revealed a c.673_1G>C homozygous class 2 (splice site) variation in intron 9. The consanguineous parents were sequenced, and both were heterozygous for the same mutation. This variation has not been previously reported in the literature. In conclusion, a 46,XY DSD should be considered in patients with a female phenotype who exhibit gonad(s) in the inguinal area at an early age. Furthermore, in patients with insufficient T synthesis and high levels of androstenedione, 17ß-HSD3 should be considered, and molecular analysis should be done for a definitive diagnosis and subsequent genetic counseling.

Indel mutations within the bovine HSD17B3 gene are significantly associated with ovary morphological traits and mature follicle number.

Given the intensive selection for increased milk production, it is imperative that the problem of declining fertility in dairy cows be reversed. In female mammals their reproductive traits and functioning is controlled by a finely tuned process balancing estrogens and androgens, in which androgens (e.g., testosterone) as a precursor substance can participate in estrogen synthesis by activating 17ß-hydroxysteroid dehydrogenase (17betaHSD). Being a key catalyst for testosterone synthesis, we hypothesized HSD17B3 gene is involved in the ovary's development and thereby capable of influencing cows' fecundity. Herein, to investigate the relationship between polymorphisms of the HSD17B3 gene and cow fertility, we characterized three insertion/deletion (indels) polymorphisms of this gene in 1110 healthy bovine ovaries. Their respective minimum allelic frequency (MAF) ranged from 0.180 to 0.482. For the ovary morphological traits, correlations revealed that both P1-D15-bp and P4-D19-bp demonstrated significant associations with ovarian height (P = 0.007 and 0.004, respectively), while P5-I5-bp was found to be significantly associated with the ovarian weight (P = 0.024). For ovarian volume, a significant correlation was uncovered between it and both polymorphisms of P4-D19-bp (P = 0.036) and P5-I5-bp (P = 0.045). Cows with either the DD genotype of P4-D19-bp or P5-I5-bp tended to have greater ovarian volume, a result consistent with their relationship to ovarian weight (P5-I5-bp) or height (P4-D19-bp). For the mature follicle traits, polymorphisms of P4-D19-bp were found significantly associated with the number of mature follicles (P = 0.045). Furthermore, expression levels of HSD17B3 differed significantly between the maximal and minimum groups of ovarian weight or volume, and the transcription factors GATA-1 and USF were predicted to bind P1-D15-bp and P4-D19-bp, respectively. This suggested the detected intron mutations could affect HSD17B3's transcription by regulating the binding of transcription factors, thereby affecting ovarian weight and other reproductive traits. As a potential effective molecular marker loci significantly related to traits of ovary and follicle, these three indels could be used in practical molecular marker-assisted selection (MAS) breeding programs, to optimize female fertility and enhance economic efficiency in the dairy cow industry.

Detection of 46, XY Disorder of Sex Development (DSD) Based on Plasma Cell-Free DNA and Targeted Next-Generation Sequencing.

Mutations in the HSD17B3 gene cause HSD17B3 deficiency and result in 46, XY Disorders of Sex Development (46, XY DSD). The diagnosis of 46, XY DSD is very challenging and not rarely is confirmed only at older ages, when an affected XY female presents with primary amenorrhea or develops progressive virilization. The patient described in this paper represents a case of discrepancies between non-invasive prenatal testing (NIPT) and ultrasound based fetal sex determination detected during prenatal screening. Exome sequencing was performed on the cell free fetal DNA (cffDNA), amniotic fluid, and the parents. Libraries were generated according to the manufacturer's protocols using TruSight One Kits (Illumina Inc., San Diego, CA, USA). Sequencing was carried out on NEXT Seq 500 (Illumina) to mean sequencing depth of at least 100×. A panel of sexual disease genes was used in order to search for a causative variant. The finding of a mutation (c.645 A>T, p.Glu215Asp) in HSD17B3 gene in amniotic fluid as well as in cffDNA and both parents supported the hypothesis of the HSD17B3 deficiency. In conclusion, we used clinical exome sequencing and non-invasive prenatal detection, providing a solution for NIPT of a single-gene disorder. Early genetic diagnoses are useful for patients and clinicians, contribute to clinical knowledge of DSD, and are invaluable for genetic counseling of couples contemplating future pregnancies.

46,XY Disorder of Sex Development due to 17-Beta Hydroxysteroid Dehydrogenase Type 3 Deficiency in an Infant of Greek Origin.

17-beta hydroxysteroid dehydrogenase type 3 (17ßHSD-3) enzyme catalyzes the conversion of androstenedione (Δ4) to testosterone (T) in the testes of the developing fetus, thus playing a crucial role in the differentiation of the gonads and in establishing the male sex phenotype. Any mutation in the encoding gene (HSD17B3) can lead to varying degrees of undervirilization of the affected male, ranging from completely undervirilized external female genitalia to predominantly male with micropenis and hypospadias. We present here an infant who was referred to our clinic because of ambiguous genitalia at birth. Gonads were palpable in the inguinal canal bilaterally and no Müllerian structures were identified on pelvic ultrasound. Because of a low T/Δ4 ratio after a human chorionic gonadotropin stimulation test, a tentative diagnosis of 17ßHSD-3 deficiency was made which was confirmed after genetic analysis of the HSD17B3 gene of the patient. The molecular analysis identified compound heterozygosity of two previously described mutations and could offer some further validation for the idea of a founder effect for 655-1;G→A mutation in the Greek population.

17ß-Hydroxysteroid dehydrogenase 3 deficiency: Three case reports and a systematic review.

17ß-Hydroxysteroid dehydrogenase 3 deficiency is a rare autosomal recessive cause of 46, XY disorders of sex development resulting from HSD17B3 gene mutations, however, no case has been reported in East Asia. The aim of this study was to report three Chinese 46, XY females with 17ß-HSD3 deficiency in a single center and perform a systematic review of the literature. Clinical examination, endocrine evaluation and HSD17B3 gene sequencing were performed in the three Chinese phenotypically females (two sisters and one unrelated patient). Relevant articles were searched by using the term "HSD17B3" OR "17beta-HSD3 gene" with restrictions on language (English) and species (human) in Pubmed and Embase. All the three phenotypically female subjects showed 46, XY karyotype, inguinal masses, decreased testosterone and increased androstenedione. Two novel homozygous mutations (W284X and c.124_127delTCTT) in HSD17B3 gene were identified. A systematic review found a total of 121 pedigrees/158 patients, with 78.5% (124/158) of patients assigned as females, 15.2% (24/158) from females to males, and 5.1% (8/158) raised as males. The most common mutation was c.277+4C>T (allele frequency: 25/72) for patients from Europe, and R80Q (allele frequency: 21/54) for patients from West Asia. The testicular histology showed normal infantile testicular tissue in 100% (9/9) infantile patients, normal quantity germ cells in 44.4% (8/18) prepubertal patients and 19.0% (4/21) pubertal and adult patients. We reported the first East Asian 17ß-hydroxysteroid dehydrogenase 3 deficiency cases. Additional literature reviews found founder effects among patients with different ethnic background and early orchiopexy may benefit fertility in patients assigned as males. These findings may significantly expand the clinical, ethnic and genetic spectrum of 17ß-hydroxysteroid dehydrogenase 3 deficiency.

Novel mutations of HSD17B3 in three Chinese patients with 46,XY Disorders of Sex Development.

17ß-Hydroxysteroid dehydrogenase type 3 (17ß-HSD3) converts the inactive Δ4-androstenedione (A) to testosterone (T). Its deficiency is the most common testosterone biosynthesis defect that results in 46,XY Disorders Of Sex Development (DSD). However, the disease is difficult to distinguish from other 46,XY DSD for similar clinical phenotypes. Therefore, genetic testing provides good criteria for the diagnosis of the disease. In this study, HSD17B3 gene was examined in 3 unrelated Chinese patients with 46,XY DSD. Direct sequencing and quantitative PCR of HSD17B3 gene revealed the presence of a compound heterozygous mutation (p.I60T/exon1 deletion) in Patient 1, a homozygous (p.I60T) mutation in Patient 2 and a frameshift mutation (p.V25Efs∗54) and an exon1 deletion in Patient 3. All of the mutations have not been reported previously. These novel mutations may expand the mutation database of HSD17B3 gene and provide us new insights into the molecular mechanism of 17ß-HSD3 deficiency. It is noteworthy that when direct sequence analysis showed a rare homozygous mutation in patients with non-consanguineous parents, "apparent homozygosity" should be taken into an account and the intragenic deletion should be screened. In addition, when single mutation was found in patients with disease in recessive heredity mode, the intragenic deletion should also be screened.

46,XY disorder of sex development (DSD) due to 17ß-hydroxysteroid dehydrogenase type 3 deficiency.

17ß-hydroxysteroid dehydrogenase 3 deficiency consists of a defect in the last phase of steroidogenesis, in which androstenedione is converted into testosterone and estrone into estradiol. External genitalia range from female-like to atypical genitalia and most affected males are raised as females. Virilization in subjects with 17ß-HSD3 deficiency occurs at the time of puberty and several of them change to male social sex. In male social sex patients, testes can be safely maintained, as long as they are positioned inside the scrotum The phenotype of 46,XY DSD due to 17ß-HSD3 deficiency is extremely variable and clinically indistinguishable from other causes of 46,XY DSD such as partial androgen insensitivity syndrome and 5α-reductase 2 deficiency. Laboratory diagnosis is based on a low testosterone/androstenedione ratio due to high serum levels of androstenedione and low levels of testosterone. The disorder is caused by a homozygous or compound heterozygous mutations in the HSD17B3 gene that encodes the 17ß-HSD3 isoenzyme leading to an impairment of the conversion of 17-keto into 17-hydroxysteroids. Molecular genetic testing confirms the diagnosis and provides the orientation for genetic counseling. Our proposal in this article is to review the previously reported cases of 17ß-HSD3 deficiency adding our own cases.

A Novel Mutation Causing 17-ß-Hydroxysteroid Dehydrogenase Type 3 Deficiency in an Omani Child: First Case Report and Review of Literature.

This is the first case report in Oman and the Gulf region of a 17-ß-hydroxysteroid dehydrogenase type 3 (17-ß-HSD3) deficiency with a novel mutation in the HSD17B3 gene that has not been previously described in the medical literature. An Omani child was diagnosed with 17-ß-HSD3 deficiency and was followed up for 11 years at the Pediatric Endocrinology Clinic, Royal Hospital, Oman. He presented at the age of six weeks with ambiguous genitalia, stretched penile and bilateral undescended testes. Ultrasound showed no evidence of any uterine or ovarian structures with oval shaped solid structures in both inguinal regions that were confirmed by histology to be testicular tissues with immature seminiferous tubules only. The diagnosis was made by demonstrating low serum testosterone and high androstenedione, estrone, and androstenedione:testosterone ratio. Karyotyping confirmed 46,XY and the infant was raised as male. Testosterone injections (25mg once monthly) were given at two and six months and then three months before his surgeries at five and seven years of age when he underwent multiple operations for orchidopexy and hypospadias correction. At the age of 10 years he developed bilateral gynecomastia (stage 4). Laboratory investigations showed raised follicle-stimulating hormone, luteinizing hormone, androstenedione, and estrone with low-normal testosterone and low androstendiol glucurunide. Testosterone injections (50mg once monthly for six months) were given that resulted in significant reduction in his gynecomastia. Molecular analysis revealed a previously unreported homozygous variant in exon eight of the HSD17B3 gene (NM_000197.1:c.576G>A.Trp192*). This variant creates a premature stop codon, which is very likely to result in a truncated protein or loss of protein production. This is the first report in the medical literature of this novel HSD17B3 gene mutation. A literature review was conducted to identify the previous studies related to this disorder.