From exome analysis in idiopathic azoospermia to the identification of a high-risk subgroup for occult Fanconi anemia.

PURPOSE: In about 10% of patients affected by Fanconi anemia (FA) the diagnosis is delayed until adulthood, and the presenting symptom in these "occult" FA cases is often a solid cancer and cancer treatment-related toxicity. Highly predictive clinical parameter(s) for diagnosing such an adult-onset cases are missing. METHODS: (1) Exome sequencing (ES), (2) Sanger sequencing of FANCA, (3) diepoxybutane (DEB)-induced chromosome breakage test. RESULTS: ES identified a pathogenic homozygous FANCA variant in a patient affected by Sertoli cell-only syndrome (SCOS) and in his azoospermic brother. Although they had no overt anemia, chromosomal breakage test revealed a reverse somatic mosaicism in the former and a typical FA picture in the latter. In 27 selected SCOS cases, 1 additional patient showing compound heterozygous pathogenic FANCA variants was identified with positive chromosomal breakage test. CONCLUSION: We report an extraordinarily high frequency of FA in a specific subgroup of azoospermic patients (7.1%). The screening for FANCA pathogenic variants in such patients has the potential to identify undiagnosed FA before the appearance of other severe clinical manifestations of the disease. The definition of this high-risk group for "occult" FA, based on specific testis phenotype with mild/borderline hematological alterations, is of unforeseen clinical relevance.

Male infertility in Sertoli cell-only syndrome: An investigation of autosomal gene defects.

OBJECTIVES: To detect autosomal genetic defects and to determine candidate genes in Sertoli cell-only syndrome infertile men. METHODS: Single-nucleotide polymorphism + comparative genomic hybridization microarray technology was carried out on 39 Sertoli cell-only syndrome infertile patients in the present study. Array comparative genomic hybridization compares the patient's genome against a reference genome, and identifies uncover deletions, amplifications and loss of heterozygosity. RESULTS: A link between defective spermatogenesis genes and infertility was examined, and amplifications and deletions in several genes were detected, including homeobox gene; synaptonemal complex element protein 1; collagen, type I, alpha 1; imprinted maternally expressed transcript; and potassium voltage-gated channel subfamily Q member 1. CONCLUSIONS: The present data suggest that several genes can play an important role in spermatogenesis and progression of Sertoli cell-only syndrome.

Noonan syndrome males display Sertoli cell-specific primary testicular insufficiency.

Context Abnormalities in the hypothalamo-pituitary-gonadal axis have long been reported in Noonan syndrome (NS) males with only few data available in prepubertal children. Objective The aim of this study was to describe the gonadal function of NS males from childhood to adulthood. Design It is a retrospective chart review. Patients and methods A total of 37 males with a genetically confirmed diagnosis of NS were included. Clinical and genetic features, as well as serum hormone levels (LH, FSH, testosterone, anti-Müllerian hormone (AMH), and inhibin B) were analysed. Results Of the 37 patients, 16 (43%) children had entered puberty at a median age of 13.5 years (range: 11.4-15.0 years); age at pubertal onset was negatively correlated with BMI SDS (r = -0.541; P = 0.022). In pubertal boys, testosterone levels were normal suggesting a normal Leydig cell function. In contrast, NS patients had significant lower levels of AMH (mean SDS: -0.6 ± 1.1; P = 0.003) and inhibin B (mean SDS: -1.1 ± 1.2; P < 0.001) compared with the general population, suggesting a Sertoli cell dysfunction. Lower AMH and inhibin B levels were found in NS-PTPN11 patients, whereas these markers did not differ from healthy children in SOS1 patients. No difference was found between cryptorchid and non-cryptorchid patients for AMH and inhibin B levels (P = 0.43 and 0.62 respectively). Four NS-PTPN11 patients had a severe primary hypogonadism with azoospermia/cryptozoospermia. Conclusions NS males display Sertoli cell-specific primary testicular insufficiency, whereas Leydig cell function seems to be unaffected.

Sperm retrieval and live birth rates in presumed Sertoli-cell-only syndrome in testis biopsy: a single centre experience.

We aimed to investigate sperm retrieval rates (SRR) by testicular sperm extraction (TESE), factors affecting SRR, and fertilization rate (FR), implantation rate (IR), clinical pregnancy rate (CPR) and live birth rate (LBR) in patients with presumed Sertoli-cell-only syndrome in testis biopsy (SCOS). We retrospectively evaluated files of 134 patients with SCOS who underwent TESE. Group I were patients in whom spermatozoa were retrieved and Group II were patients in whom no spermatozoa could be retrieved. SRR, Follicle stimulating hormone (FSH), Luteinizing hormone (LH), and testosterone levels, and the volume of testicles were compared between groups. In addition, FR, IR, CPR and LBR were determined. Sperm retrieval was achieved in 37 (27.6%) patients (Group I), and the remaining 97 (72.4%) patients made Group II. There were no significant differences in age, infertility time, testicular volume, serum FSH, LH and testosterone levels between Groups I and II (p > 0.05). Intracytoplasmic sperm injection (ICSI) was performed in 36 patients. FR, IR, and CPR were 60.86 ± 23.03, 36.53 ± 41.78 and 51.3% respectively. Cycle and patient based LBRs were 37.8 and 45.1% respectively. SRR in SCOS is lower than patients with non-obstructive azoospermia (NOA) in general. No parameters to predict spermatozoa retrieval were determined. In patients with SCOS, ICSI achieves similar live birth rate to other patients with NOA.