OBJECTIVETo investigate the chromosome segregation patterns in patients with chromosome balanced translocation in spermatogenesis and to find out different proportions of abnormal sperm generated by different patterns.

METHODSTriple color fluorescence in-situ hybridization (FISH) was used to determine the correlative chromosome constitution of spermatozoa from 4 patients with chromosome anomalies, Case 1 with 46, XY, t(9;11)(q22;q21), Case 2 with 46, XY, t(11;22) (q23;q11), Case 3 with 45, XY, t(13q;15q) and Case 4 with 45, XY, t(13q;14q). The numbers of spermatozoa generated by different chromosome segregation patterns were counted by FISH, and normal sperm from the males with normal chromosome was used as control.

RESULTSThe rates of abnormal sperm in the 4 cases were 50.86%, 58.33%, 13.00% and 22.82% respectively, evidently higher than their corresponding controls (0.85%, 1.63%, 1.60% and 1.37%).

CONCLUSIONTo detect sperm chromosome in patients with chromosome balanced translocation by FISH can provide valuable information for predicting the risk of chromosome anomalies in the embryo preimplantation genetic diagnosis.