Laboratorio di Genetica Umana, E.O. Ospedali Galliera, Genova, Italy.
J Appl Genet. 2012 Aug;53(3):285-8. doi: 10.1007/s13353-012-0097-x. Epub 2012 Apr 29.
Complex chromosomal rearrangements (CCRs) are structural aberrations involving more than two chromosomes with at least three breakpoints. CCRs can be divided into familial and de novo. Balanced CCR are extremely rare in humans and are at high risk of producing unbalanced gametes. Individuals with balanced CCR are usually phenotipically normal but report fertility problems, recurrent miscarriages or congenital anomalies in newborn offsprings as consequence of either meiotic failure or imbalanced chromosomes segregation.We describe the case of an unbalanced CCR involving chromosomes 1, 4 and 8 found in a girl with developmental delay, hexadactilia and microcephaly. The rearrangement, apparently balanced at a standard karyotype analysis and of maternal origin, was demonstrated to be unbalanced by array-CGH and FISH. In conclusion our study underlines the importance of the combined use of a quantitative technique, as array-CGH, to detect criptic segmental aneuploidies, and a qualitative tool, as FISH analysis, to physically map the localization of the chromosome segments involved, in order to realize the exact nature that underlies a chromosomal rearrangement.
复杂染色体重排（CCRs）是涉及三个以上断点的两种以上染色体的结构异常。CCRs 可分为家族性和新生性。平衡 CCR 在人类中极为罕见，并且极易产生不平衡的配子。携带平衡 CCR 的个体通常表型正常，但由于减数分裂失败或不平衡染色体分离，会导致生育问题、反复流产或新生儿先天异常。我们描述了一例涉及 1、4 和 8 号染色体的不平衡 CCR，该病例发生在一名发育迟缓、六指畸形和小头畸形的女孩中。该重排似乎在标准核型分析中平衡且来自母体，通过 array-CGH 和 FISH 证实为不平衡。总之，我们的研究强调了联合使用定量技术（如 array-CGH）检测隐匿性片段性非整倍体，以及使用定性工具（如 FISH 分析）物理定位涉及的染色体片段的重要性，以确定染色体重排所涉及的精确性质。
