Analytical validation and chromosomal distribution of regions of homozygosity by oligonucleotide array comparative genomic hybridization from normal prenatal and postnatal case series

作者：Jiadi Wen, Kathleen Comerford, Zhiyong Xu, Weiqing Wu, Katherine Amato, Brittany Grommisch, Autumn DiAdamo, Fang Xu, Hongyan Chai, Peining Li · 发表于：Molecular Cytogenetics · 年份：2019 · DOI：10.1186/s13039-019-0424-6 · 被引用次数：9 · 研究领域：Genomic variations and chromosomal abnormalities、Genetic Associations and Epidemiology、Genomics and Rare Diseases

BACKGROUND: Regions of homozygosity (ROH) are continuous homozygous segments commonly seen in the human genome. The integration of single nucleotide polymorphism (SNP) probes into current array comparative genomic hybridization (aCGH) analysis has enabled the detection of the ROH. However, for detecting and reporting biologically relevant ROH in a clinical setting, it is necessary to assess the analytical validity of SNP calling and the chromosomal distribution of ROH in normal populations. METHODS: The analytical validity was evaluated by correlating the consistency of SNP calling with the quality parameters of aCGH and by accessing the accuracy of SNP calling using PCR based restriction enzyme digestion and Sanger sequencing. The distribution of ROH was evaluated by the numbers, sizes, locations, and frequencies of ROH from the collection of data from parental, postnatal, and prenatal case series that had normal aCGH and chromosome results. RESULTS: The SNP calling failure rate was 20-30% with a derivative Log2 ratio (DLR) below 0.2 and increased significantly to 30-40% with DLR of 0.2-0.4. The accuracy of SNP calling is 93%. Of the 958 cases tested, 34% had no ROH, 64% had one to four ROH, and less than 1% had more than five ROH. Of the 1196 ROH detected, 95% were less than 10 Mb. The distribution of numbers and sizes of ROH showed no differences among the parental, pediatric and prenatal case series and test tissues. The chromosomal distribution of ROH was non-random with...