GnRH Deficient Patients With Congenital Hypogonadotropic Hypogonadism: Novel Genetic Findings in ANOS1, RNF216, WDR11, FGFR1, CHD7, and POLR3A Genes in a Case Series and Review of the Literature
Authors: Vassos Neocleous, Pavlos Fanis, Meropi Toumba, George A Tanteles, Melpo Schiza, Feride Cinarli, Nicolas C Nicolaides, Anastasis Oulas, George M Spyrou, Christos S Mantzoros, Dimitrios Vlachakis, Nicos Skordis, Leonidas A Phylactou
Journal: Front Endocrinol (Lausanne) (2020)
Keywords: gnrh, digenic inheritance, genes, hypogonadotropic hypogonadism, next generation sequencing
MeSH terms: DNA Helicases / genetics, DNA-Binding Proteins / genetics, Extracellular Matrix Proteins / genetics, Gonadotropin-Releasing Hormone / deficiency, Hypogonadism / genetics, Membrane Proteins / genetics, Nerve Tissue Proteins / genetics, Proto-Oncogene Proteins / genetics, RNA Polymerase III / genetics, Receptor, Fibroblast Growth Factor, Type 1 / genetics, Ubiquitin-Protein Ligases / genetics, Research Support, Non-U.S. Gov't, Adolescent, Adult, Aged, Female, High-Throughput Nucleotide Sequencing, Humans, Male, Mutation, Pedigree, Retrospective Studies, Young Adult, ANOS1 protein, human, DNA-Binding Proteins, Extracellular Matrix Proteins, Membrane Proteins, Nerve Tissue Proteins, Proto-Oncogene Proteins, WDR11 protein, human, Gonadotropin-Releasing Hormone, RNF216 protein, human, Ubiquitin-Protein Ligases, Receptor, Fibroblast Growth Factor, Type 1, POLR3A protein, human, RNA Polymerase III, DNA Helicases, CHD7 protein, human

Background: Congenital hypogonadotropic hypogonadism (CHH) is a rare genetic disease caused by Gonadotropin-Releasing Hormone (GnRH) deficiency. So far a limited number of variants in several genes have been associated with the pathogenesis of the disease. In this original research and review manuscript the retrospective analysis of known variants in ANOS1 (KAL1), RNF216, WDR11, FGFR1, CHD7, and POLR3A genes is described, along with novel variants identified in patients with CHH by the present study. Methods: Seven GnRH deficient unrelated Cypriot patients underwent whole exome sequencing (WES) by Next Generation Sequencing (NGS). The identified novel variants were initially examined by in silico computational algorithms and structural analysis of their predicted pathogenicity at the protein level was confirmed. Results: In four non-related GnRH males, a novel X-linked pathogenic variant in ANOS1 gene, two novel autosomal dominant (AD) probably pathogenic variants in WDR11 and FGFR1 genes and one rare AD probably pathogenic variant in CHD7 gene were identified. A rare autosomal recessive (AR) variant in the SRA1 gene was identified in homozygosity in a female patient, whilst two other male patients were also, respectively, found to carry novel or previously reported rare pathogenic variants in more than one genes; FGFR1/POLR3A and SRA1/RNF216. Conclusion: This report embraces the description of novel and previously reported rare pathogenic variants in a series of genes known to be implicated in the biological development of CHH. Notably, patients with CHH can harbor pathogenic rare variants in more than one gene which raises the hypothesis of locus-locus interactions providing evidence for digenic inheritance. The identification of such aberrations by NGS can be very informative for the management and future planning of these patients.