Sperm chromosome analysis in a man heterozygous for a paracentric inversion of chromosome 7 (q11q22).
Human sperm chromosomes were studied in a man heterozygous for a paracentric inversion of chromosome 7 (q11q22). The pronuclear chromosomes were analysed after in vitro penetration of golden hamster (Mesocricetus auratus) eggs. Ninety-four sperm chromosome spreads were examined, of which 34 contained the normal number 7 chromosome and 59 the inverted 7. This segregation was significantly different from the expected 1:1 ratio. The number of X- to Y-bearing sperm was 48 and 46 respectively. No sperm contained a recombinant chromosome caused by a crossover within the inversion. The frequency of chromosomal abnormalities in other chromosomes was 9.6%, which is not significantly different from the frequency observed in normal donors (8.9%) in our laboratory. These results suggest that the risk of chromosomally unbalanced sperm is not high for this paracentric inversion.
D000818:Animals; D002871:Chromosome Banding; D007446:Chromosome Inversion; D002906:Chromosomes, Human, 6-12 and X; D006224:Cricetinae; D005260:Female; D006579:Heterozygote; D006801:Humans; D007621:Karyotyping; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000648:ultrastructure*