[Male infertility of chromosomal origin]

Cytogenetic studies in infertile men showed that chromosomal anomalies were more frequent in these patients than in general population. Sex chromosome anomalies, specially 47, XYY karyotype, are predominant by their frequency at the severity of testicular impair. Nevertheless, balanced autosomal rearrangements can also induce spermatogenic failure; they were of great interest in perfecting the hypothesis which try to explain germ cells atresia. Three mechanisms are proposed: --X-autosome interaction; --synaptic failure; both could lead to a metabolic disorder and death of the germ cell; --somatic lesions of the gonad could also induce this degenerative process. Techniques of molecular biology joined up to cytogenetic investigations of meiosis will lead to a better understanding of the chromosomal male sterility.