Analysis of sperm chromosome complements from a man heterozygous for a pericentric inversion, inv(8)(p23q22)

Human sperm chromosomes were studied in a man heterozygous for a pericentric inversion (p23q22) of chromosome 8. The pronuclear chromosomes were analyzed after in vitro penetration of golden hamster eggs. A total of 166 sperm were examined; 88.6% were chromosomally balanced and 11.4% were recombinant. Of the balanced complements, the proportion with a normal chromosome 8 (53.6%) was approximately equal to the proportion with an inverted 8 (46.4%). Of the recombinant complements, the proportion of sperm with a duplication of 8q and a deletion of 8p (5.7%) was equal to the reciprocal event of a duplication of 8p and a deletion of 8q (5.7%). The frequencies of X-bearing (53.2%) and Y-bearing sperm (46.8%) were not significantly different from the expected 1:1 ratio. There was no evidence for an interchromosomal effect. A total of four pericentric inversions have been studied by human sperm chromosome analysis; recombinant chromosomes have been observed in two of the four cases.