[Incidence of structural chromosomal abnormalities in spermatogenesis in man]

Infertility due to gametogenic failure is frequently associated with structural autosomal abnormalities. Recent meiotic studies at the pachytene stage undertaken in human infertile heterozygous carriers for such rearrangements have regularly shown a synaptic failure around the breakpoints, an association of the translocation figure with the sex chromosomes and the frequent involvement of the acrocentric chromosomes. Two main models were proposed to explain the male sterilizing effect of autosomal rearrangements: the impairment of spermatogenesis could be the result of: 1) the XY-autosome interaction; 2) the pairing disruption around the breakpoints at the pachytene stage. They could contribute significantly to germ-cell atresia.