Cytogenetics and Molecular Genetics Unit - Bambino Gesù Children's Hospital, Rome 00165, Italy.
Orphanet J Rare Dis. 2011 Apr 19;6:17. doi: 10.1186/1750-1172-6-17.
Complex chromosome rearrangements are constitutional structural rearrangements involving three or more chromosomes or having more than two breakpoints. These are rarely seen in the general population but their frequency should be much higher due to balanced states with no phenotypic presentation. These abnormalities preferentially occur de novo during spermatogenesis and are transmitted in families through oogenesis.Here, we report a de novo complex chromosome rearrangement that interests eight chromosomes in eighteen-year-old boy with an abnormal phenotype consisting in moderate developmental delay, cleft palate, and facial dysmorphisms.Standard G-banding revealed four apparently balanced translocations [corrected] involving the chromosomes 1;13, 3;19, 9;15 and 14;18 that appeared to be reciprocal. Array-based comparative genomic hybridization analysis showed no imbalances at all the breakpoints observed except for an interstitial microdeletion on chromosome 15. This deletion is 1.6 Mb in size and is located at chromosome band 15q14, distal to the Prader-Willi/Angelman region. Comparing the features of our patient with published reports of patients with 15q14 deletion this finding corresponds to the smallest genomic region of overlap. The deleted segment at 15q14 was investigated for gene content.
复杂染色体重排是指涉及三个或更多染色体或具有两个以上断裂点的结构性染色体重排。这些在普通人群中很少见,但由于平衡状态没有表型表现,其频率应该更高。这些异常主要在精子发生过程中从头发生,并通过卵母细胞在家族中传递。在这里,我们报告了一例 18 岁男孩的新发复杂染色体重排,该男孩具有异常表型,包括中度发育迟缓、腭裂和面部畸形。标准 G 带显示四条明显平衡的易位[已纠正],涉及染色体 1;13、3;19、9;15 和 14;18,似乎是相互的。基于阵列的比较基因组杂交分析显示,在观察到的所有断点处均无不平衡,除了 15 号染色体上的一个染色体间微缺失。该缺失大小为 1.6Mb,位于 15q14 染色体带,靠近 Prader-Willi/Angelman 区域。将我们患者的特征与发表的 15q14 缺失患者的报告进行比较,这一发现对应于最小的基因组重叠区域。对 15q14 缺失的片段进行了基因含量的研究。