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近年来对染色体脆性部位的研究非常广泛,但除了fraXq27已肯定与遗传性智力低下等症状有关外,其它脆性位点的表达很少伴有临床症状。许多报道指出核型中某些染色体的重排和断裂常与脆性部位靠近或吻合,目前虽还不能得到明确的结论,但多数报道认为肿瘤细胞中断裂点与脆性位点有相关性。习惯性流产者染色体异常频率大约为4%左右,而流产儿及其死胎中所发现的染色体异常频率却高达50
In recent years, the study of the chromosomal fragile sites is very extensive, but in addition to the fraXq27 has certainly associated with genetic mental retardation and other symptoms, the expression of other fragile sites is rarely associated with clinical symptoms. Many reports point out that the rearrangement and rupture of certain chromosomes in karyotypes are often close to or coincidental with the fragile sites. Although no clear conclusion can be reached yet, most reports suggest that there is a correlation between the breakpoints in tumor cells and the sites of fragility. The frequency of chromosomal abnormalities in habitual abortion is about 4%, while the frequency of chromosomal abnormalities found in aborted children and stillbirths is as high as 50