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Background The routine genetic analysis for diagnosing male infertility has not changed over the last twenty years, and currently available tests can only determine the etiology of 4% of unselected infertile patients. Thus, to create new diagnostic assays, we must better understand the molecular and genetic mechanisms of male infertility. Although next‐generation sequencing allows for simultaneous analysis of hundreds of genes and the discovery of novel candidates related to male infertility, so far only a few gene candidates have enough sound evidence to support the gene–disease relationship. Objective Since complementary studies are required to validate genes, we aimed to analyze the presence of potentially pathogenic rare variants in a set of candidate genes related to azoospermia in a hitherto understudied South American population. Subjects and Methods We performed whole exome sequencing in a group of 16 patients with non‐obstructive azoospermia from Ribeirão Preto, Brazil. Based on a recent systematic review of monogenic causes of male infertility, we selected a set of 37 genes related to azoospermia, Sertoli‐Cell‐Only histology, and spermatogenic arrest to analyze. The identified variants were confirmed by Sanger sequencing, and their functional consequence was predicted by in silico programs. Results We identified potential pathogenic variants in seven genes in six patients. Two variants, c.671A>G (p.(Asn224Ser)) in DMRT1 and c.91C>T (p.(Arg31Cys)) in REC8, have already been described in association with azoospermia. We also found new variants in genes that already have moderate evidence of being linked to spermatogenic failure (TEX15, KLHL10), in genes with limited evidence (DNMT3B, TEX14) and in one novel promising candidate gene that has no evidence so far (SYCE1L). Discussion Although this study included a small number of patients, the process of rationally selecting genes allowed us to detect rare potentially pathogenic variants, providing supporting evidence for validating candidate genes associated with azoospermia.

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The molecular basis of anhydrobiosis, the state of suspended animation entered by some species during extreme desiccation, is still poorly understood despite a number of transcriptome and proteome studies. We therefore conducted functional screening by RNA interference (RNAi) for genes involved in anhydrobiosis in the holo-anhydrobiotic nematode Panagrolaimus superbus. A new method of survival analysis, based on staining, and proof-of-principle RNAi experiments confirmed a role for genes involved in oxidative stress tolerance, while a novel medium-scale RNAi workflow identified a further 40 anhydrobiosis-associated genes, including several involved in proteostasis, DNA repair and signal transduction pathways. This suggests that multiple genes contribute to anhydrobiosis in P. superbus.