一例13号环状染色体综合征患儿的临床及遗传学分析

患儿，女，5个月，因生长发育迟缓就诊，体格检查发现体格发育落后，特殊面容（小头畸形、眼距宽、耳位偏低、鼻梁扁平、短人中）以及一侧小阴唇缺失。外周血染色体核型为46，XX，r（13）（p11q33）82]/45，XX，-1310]/46，XX，r（13；13）（p11q33；p11q33）8]；微阵列比较基因组杂交（aCGH）检测显示13q11q33.2区域和13q33.2q34区域分别有87.5 Mb的重复和8.2 Mb的缺失；荧光原位杂交（FISH）显示13号环状染色体长臂末端缺失。诊断为13号环状染色体综合征。该综合征临床表型多变，主要与染色体区带中遗传物质丢失的数量、部位以及不同核型嵌合比例不同等密切相关。

Clinical and genetic features of ring chromosome 13 syndrome: an analysis of one case

A girl aged 5 months was admitted due to developmental delay. Physical examination showed delayed physical development, unusual facies (microcephalus, hypertelorism, low-set ears, wide nasal bridge, and short philtrum), and an absence of the labium minus at one side. The peripheral blood karyotype was 46,XX,r(13)(p11q33)82]/45,XX,-1310]/46,XX,r(13;13)(p11q33;p11q33)8], and array-based comparative genomic hybridization showed an 87.5 Mb duplication in 13q11q33.2 region and an 8.2 Mb deletion in 13q33.2q34 region. Fluorescence in situ hybridization showed terminal depletion of the long arm of the ring chromosome 13. The girl was diagnosed with ring 13 syndrome. This syndrome has various clinical phenotypes and is closely associated with the amount and site of the loss of genetic material in chromosomal band and different rates of chimerism.