5号和18号染色体变异致多发畸形的临床报道和遗传学分析

目的明确一例多发畸形患儿染色体拷贝数变异的性质，分析其染色体变异与表型的相关性。方法首先应用常规G显带分析该例患儿外周血染色体改变，然后应用比较基因组杂交芯片（array comparative genomic hybridization, array CGH ）对该例常规核型分析的结果进行精确定位。结果该患儿常规核型分析为46，XY，inv（9）（p12q13），Yqh＋。arrayCGH结果为dup（5）（p14．1p15．33）区段（151，737—28，789，424）存在28．64Mb重复；del（18）（q22．1q23）区段（63，993，067—77，982，126）存在13．99Mb缺失。临床表现为面容特殊、眼裂小、牙齿反颌、隐形脊柱裂及脚趾畸形等。结论5号和18号染色体拷贝数变异可导致患儿出现多发畸形；与传统的细胞遗传学分析方法相比，arrayCGH在染色体异常分析中具有更高的分辨率和准确性。

Chromosome .5 and 18 variation caused multi- malformation and research by phenotype and genetic analysis.

Objective： To determine the origin of chromosomal aberrants in a multi - malformation children, and to correlate the karyotype with phenotype. Methods ： Routine G - banding were performed to analyze the karyotype of the patient and her parents, and array comparative genomic hybridization （array CGH） were used for finely mapping the aberrant regions. Results： The karyotype of the child was ascertained as 46, XY, inv （9） （p12q13）, Yqh ＋. Array CGH finely mapped the duplication to 5p p14. 1 p15.33, a 28.64 Mb region, and a small deletion to 18q22. lq23, a 13.99Mb region. The patient presented some frequently seen features such as facial features, low - set ears, hypertelorism and small palpebral fissures et al. Conclusion ： This result suggested that chro- mosome 5 and 18 copy number variation can cause multi - malformation. In contract to routine karyotype analysis, aberrant regions could be mapped by array CGH with higher resolution and accuracy.