ABSTRACT
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.
ABSTRACT
Objective To investigate the frequency of t(14;18) in different subtypes of B-cell lymphomas and the ability of the polymerase chain reaction(PCR) to detect this rearrangement in frozen samples. Methods 107 cases of B-cell lymphomas were studied using DNA extracted from fresh-frozen tissues. The DNA samples were amplified by PCR for bcl-2 MBR/JH. The products of bcl-2/JH rearrangement were hybridized with an internal olignucleotide probe of bel-2 MBR. Results The rearranged bel-2MBR/JH gene was detected in 13 of the 25(52. 0％) follicular cen ter lymphomas, according to REAL classification: 8 of 11(72. 7％) grade 1 , 2 of 5(40. 0％) grade Ⅱ , and 3 of 90 (33. 3％) grade Ⅲ. 17 of 82(20. 8％) cases of diffuse large B-cell lympbomas were found to have detectable bcl-2 MBR/JH rearrangement. Conclusion The frequency of bcl-2 MBR/JH rearrangement in diffuse large B-cell lym phomas is significantly lower than those in follicular center lymphomas(χ2=9. 28, P ＜0. 005), suggesting that bcl 2/JH rearrangements occur mainly in follicular center lymphomas. In addition, the result of reconstruction experi ments suggest that amplification of bcl-2 MBR/JH rearrangements by PCR is both sensitive and specific for detection of t (14 ; 18 ) translocation.