Tetra-Amelia with lung aplasia phenotype. Tetra-Amelia with lung aplasia phenotype

Clinical findings of this case has been reported previously by Sergio de Sousa (American Journal of Medical Genetics Part A 146A:2799–2803 (2008)). RSPO2 gene has been identified by our group (İstanbul, Turkey, 2014) as responsible gene for Tetra-Amelia with lung aplasia phenotype. To find causative pathogenic variations, sanger sequencing of fetal DNA was performed and did not reveal any variations. 300K SNP array was performed to analyse possible CNVs. A homozygous 154kb deletion on chr8 (deletion break points:108,809,266-108,963,256) covering intron 5 (partial), exon 6 and 3'UTR (partial) of RSPO2 gene was identified as the causative deletion. Overall design: Genomic DNA extracted from AF culture cells was scanned according to the array barcodes and Infinium HumanCytoSNP-12 v2.1 BeadChips datasheets (Illumina). Data was analysed with GenomeStudio Software (Illumina)

本病例的临床表型此前已由Sergio de Sousa在《美国医学遗传学杂志A辑》（American Journal of Medical Genetics Part A）2008年第146A卷第2799–2803页中报道。我们团队（土耳其伊斯坦布尔，2014年）已鉴定出RSPO2基因（RSPO2 gene）为伴肺发育不全表型的四肢全无症（Tetra-Amelia）的致病基因。为筛选致病变异，我们对胎儿DNA进行了桑格测序（Sanger sequencing），未检出任何变异。随后采用300K单核苷酸多态性芯片（Single Nucleotide Polymorphism array, SNP array）分析潜在的拷贝数变异（Copy Number Variation, CNV），最终鉴定出8号染色体上一段154kb的纯合缺失（缺失断点：108,809,266–108,963,256），该区域覆盖RSPO2基因的第5内含子（部分）、第6外显子及3'非翻译区（3'-Untranslated Region, 3'UTR）的部分序列，被确定为致病缺失。整体实验设计：从羊膜液培养细胞（Amniotic Fluid culture cells, AF culture cells）中提取基因组DNA，按照芯片条形码及Infinium HumanCytoSNP-12 v2.1 BeadChips（Illumina）的操作手册进行扫描检测，数据采用GenomeStudio软件（Illumina）完成分析。