Sister chromatid exchange frequencies in a group of individuals with unfavorable reproductive health.

Sister chromatid exchange (SCE) frequencies and other cytogenetic parameters were investigated in peripheral blood lymphocytes from 92 subjects comprising 44 parents of malformed offspring or repeated fetal wastage (Group I) and 48 controls, age and sex matched, having normal reproductive health (Group II). The karyotypes were normal and the mean mitotic indices were comparable in both groups. The mean frequency of SCE per metaphase in Group I (8.67 +/- 0.32) was significantly higher than the mean for group II (6.65 +/- 0.16), and the cellular replicative index in Group I (1.78 +/- 0.04) was significantly different from that of Group II (1.66 +/- 0.03). The results are discussed in the light of the present understanding of the etiology and mechanism of production of sister chromatid exchanges.