Characteristics of complex chromosomal rearrangement in Chinese male carriers and its impact on male fertility

CHEN Ying-jian; ZHANG Wei-wei; WU Yan-hua; SUN Xiao-ming; BAO Hui; HU Cheng-jin

doi:10.13263/j.cnki.nja.2014.12.014

Abstract：Objective:To analyze the characteristics of complex chromosomal rearrangement (CCR) in Chinese male carriers and its influence on male fertility.Methods:Using the G band technique,we conducted karyotype analysis on the peripheral blood lymphocytes of 1 625 Chinese males with reproductive problems.We also searched CNKI and Wanfang database for CCR-related literature published between January 1984 and November 2013,followed by statistical analysis on the CCR characteristics and reproductionrelated data of the CCR carriers.Results:Two CCR carriers were found among the 1 625 males and another 47 cases identified from the databases.Among the 49 CCR carriers,there were 17 three-way exchange cases (34.7％),17 double two-way exchange cases (34.7％),and 15 exceptional cases (30.6％),with no statistically significant differences in the incidence of the three types (P ＞ 0.05).Azoospermia-or oligospermia-induced infertility was found in 19 (38.8％) of the CCR carriers.A total of 87 pregnancies were achieved in the other 30 (61.2％),among which spontaneous abortion occurred in 75.9％ (66/87),dead fetus and malformed infant death in 9.2％ (8/87),and phenotypically normal offspring in 14.9％ (13/87).Recurrent abortion was associated frequently with breakpoints on CCR-involved chromosomes 6,7,8,11,and 16,while dyszoospermia mostly with breakpoints on CCR-involved chromosomes 10 and 14.The breaking occurred more than 3 times at 1p22,1q25,2q31,5p13,5q35,6q23,8q13,and 20p13.Moreover,the breakpoints at 2q31,5 q35,and 8q1 3 were particularly related to recurrent abortion,while that at 1 p22 only to dyszoospermia.Conclusion:CCR is extremely rare.Male CCR carriers are often identified through reproductive problems and have high risks of infertility and abnormal pregnancy and a very low rate of normal newborns.In addition,chromosomes and breakpoints involved in CCR may affect the fertility of male CCR carriers,and some particular chromosomal breakpoints may play a key role in gametogenesis.