背景:术语倒置是指由染色体的一个或两个臂中发现的两个断裂和融合事件引起的畸变。这种像差的存在可以,但不得与不孕症或不平衡的受孕产物有关。通常,倒位与携带者的表型改变无关。尽管大多数这样的反转都是从头和独特的,经常性断点也有报道。
方法:在至少10名无关(不育)患者中,研究了11号和12号染色体长臂中的两个反复发生的副中心倒位,以及10号染色体中的一个副中心倒位。each.通过应用基因座特异性细菌人工染色体衍生探针的荧光原位杂交缩小断点。
结果:对于所有三个研究的倒位,可以表征分子细胞遗传学上相同的断点。周心反转inv(10)(p11.21q21.2),以前报道是单一来源的,主要分布在北欧,可以发现到处都是德国,也是。在研究的病例中,在德国各地发现了近中心倒置inv(11)(q21q23.3)的复发断点,也是;然而,此外,还对两个断点略有不同的病例进行了表征。最有趣的是,反演inv(12)(q14.1~14.2q24.11~24.13)具有相同的反复断点,并介绍了在德国西北部的独家事件。
结论:总体而言,(至少)三种不同的细胞遗传学可检测的复发性倒置在这里进行了表征。这突出表明,此类事件在人群中可能比目前建议的更频繁。因此,这种事件甚至可能在(中欧)人口中传播。对此处表征的反转载流子的繁殖和适应度的特定影响似乎可以忽略不计。尽管如此,这种经常性的重新安排需要更多的关注,因为它们可能为将来的遗传咨询提供有价值的信息。
BACKGROUND: The term inversion refers to an aberration caused by two breakage and fusion events found in one or both arms of a chromosome. The presence of such aberrations can but must not be associated with infertility or unbalanced products of conception. Normally, inversions are not associated with phenotypic alterations for the carrier. Despite the fact that most such inversions are de novo and unique, recurrent breakpoints have also been reported.
METHODS: Here two recurrent paracentric inversions in the long arm of chromosomes 11 and 12 and a pericentric one in chromosome 10 were studied in at least 10 unrelated (infertile) patients, each. Breakpoints were narrowed down by fluorescence in situ hybridization applying locus-specific bacterial artificial chromosome-derived probes.
RESULTS: Molecular cytogenetically identical breakpoints could be characterized for all three studied inversions. Pericentric inversion inv(10)(p11.21q21.2), previously reported to be of single origin and distributed mainly in Northern Europe, could be found to be present all over Germany, too. In the studied cases with paracentric inversion inv(11)(q21q23.3), recurrent breakpoints were found in all parts of Germany, as well; however, additional 2 cases with slightly different breakpoints were characterized besides. Most interestingly, inversion inv(12)(q14.1∼14.2q24.11∼24.13) had always the same recurrent breakpoints and presented an exclusive occurrence in North-Western part of Germany.
CONCLUSIONS: Overall, (at least) three different cytogenetically detectable recurrent inversions were characterized here. This highlights that such events may be more frequent in human population than yet suggested. Accordingly, such events might even spread in (middle European) human population. Specific impact on reproduction and fitness of inversion carriers characterized here seems to be negligible. Nonetheless, such recurrent rearrangements need more attention as they may provide valuable information for genetic counseling in future.