一例8p倒位重复伴末端缺失综合征的表型和遗传学研究

Phenotypic and genetic analysis of a boy with inv dup del(8p)

目的明确1例发育迟缓患儿的染色体拷贝数变异性质和来源,分析其与表型的相关性。方法应用G显带染色体核型分析以及单核苷酸多态性微阵列芯片(single nucleotide polymorphism array,SNP-array)技术对患儿及其父母进行检测。结果G显带核型分析结果显示患儿的染色体核型为46,XX,add(8)(p23),其父母核型均未见异常。SNP-array分析提示患儿在8p23.1pter区存在6.78 Mb微缺失,8p23.1q11.1区域存在34.9 Mb的重复,其父母未见染色体拷贝数异常。结论确认1例8p倒位重复伴末端缺失综合征,由8p23.1上嗅觉受体(olfactory receptor,OR)基因簇发生非等位同源重组所致,可能与患儿发育迟缓表型相关。

Objective To delineate the nature and origin of a chromosomal aberration detected in a boy with mental retardation.Methods The proband and his parents were subjected to routine G-banded chromosomal karyotyping and single nucleotide polymorphism array(SNP-array)analysis.Results The karyotype of the proband was determined as 46,XX,add(8)(p23).No karyotypic abnormality was detected in either of his parents.SNP-array has identified a 34.9 Mb duplication at 8p23.1q11.1 and a 6.78 Mb microdeletion at 8p23.1pter in the proband.No copy number variation was detected in either parent.Conclusion The child was diagnosed with 8p inverted duplication deletion syndrome,which might be induced by non-allelic homologous recombination between olfactory genes in the 8p23.1 region.