Whole-exome sequencing in the complex diagnosis of genetically determined forms of male infertility associated with severe forms of pathozoospermia

In most patients with male male infertility, it's cause remains unknown. Various chromosomal abnormalities and pathogenic variants in genes controlling spermatogenesis and male fertility are involved in the etiology of azoospermia and oligozoospermia. This study is aimed to improving the effectiveness of identifying the genetic causes of male infertility. For this purpose, a sample of 200 patients with idiopathic azoospermia or severe oligozoospermia was formed and examined. A comprehensive clinical and genetic examination was performed using both conventional methods (clinical and genetic, standard cytogenetic examination, analysis of the Y chromosome microdeletions at the AZF- locus and the CFTR gene), and genomic methods - massive parallel sequencing (MPS). Using “standard” diagnostic methods, genetic causes of infertility were found in 92 (46%) patients. Whole-exome sequencing (WES) revealed variants in 29 genes involved in the control of male fertility in 18 (42.9%) of 42 patients in whom genetic factors of infertility were not detected, according to the “standard” genetic examination, of which variants in 8 genes in 7 (16.6%) patients are presumably causative and require further functional or segregation studies. Comprehensive genetic examination, including genomic methods, makes it possible to increase the effectiveness of the diagnosis of genetically determined forms of infertility.

azoospermia, oligozoospermia, male infertility, gene variants, spermatogenesis, chromosomal abnormalities

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