[Analysis for common chromosomal breakpoint regions among 586 carriers of reciprocal translocations from Henan Province].

OBJECTIVE

To determine the frequency, common chromosomal karyotypes and breakpoints, and involved regions among carriers of reciprocal translocations from Henan Province, and to explore the influence of common breakpoint regions on pregnancy and fetal development.

METHODS

For 586 carriers of reciprocal translocations, the above features were retrospectively analyzed.

RESULTS

The 586 reciprocal translocations were identified among 62 477 subjects, which yielded a frequency of 0.94%. Among these, 572 (0.92%) had abnormal fertility, and 14 (0.02%) had a history of abnormal fetal development. Statistical analysis showed that chromosomes 1, 4, 7 and 11 were most frequently involved, with t(11;22)(q25;q13) being the most common type of translocation. In total 437 breakpoint regions were identified, with 11q23, 22q13 and 1p36 being most frequently involved, which resulted in infertility, abortion, embryo death, congenital malformation, development delay, mental retardation or a normal phenotype.

CONCLUSION

Above results indicated a 0.92% carrier rate for reciprocal chromosomal translocations in Henan. The location of breakpoint regions may affect the pregnancy and/or fetal development. Discovery of such regions may enable more accurate genetic, reproductive and developmental counseling for carriers, and provide reference for delineation of function and pathogenetic mechanism of the relevant genes.