STS Gene in a Pedigree with X-linked Ichthyosis

To investigate the gene mutation in a pedigree with X-linked iehthyosis （XLI） and to explore the relationship between the mutation and its clinical manifestations, genomic DNA of affected members, the normal member of the pedigree and 50 unrelated normal members was extracted with a whole blood genomie DNA extraction kit and the DNA was used as a template for the polymerase chain reaction （PCR） mediated amplification of exon 1 and exon 10 of the STS gene. hHb6 （human hair basic keratin） gene was used as the internal control. Our results showed that the STS gene was deleted in affected members in the pedigree with X-linked ichthyosis. The normal member of the pedigree and 50 unrelated normal members had no such deletion. The proband and his mother had products in the internal control after PCR amplification. The blank control had no product. It is concluded that deletion of the STS gene existed in this pedigree with X-linked iehthyosis, and it is responsible for the unique skin lesions of X-linked ichthyosis.

A Multiplex PCR-Based Next-Generation Sequencing Approach Has Detected a Common Large Deletion in STS Gene in a Patient with X-Linked Ichthyosis

Several nuclear genes have been found to be linked to ichthyosis, and Next Generation Sequencing approach on panels of targeted genes has turned out to be particularly useful in analyzing diseases characterized by significant genetic and phenotypic heterogeneity. We developed a panel of 26 genes to be screened with the Ion Personal Genome Machine (PGM) for causative mutations relating to ichthyosis. Sequencing runs were obtained from a patient with ichthyosis using the Ion Torrent PGM and then processed with Ion Torrent Suite, Variant Caller, Coverage Analysis and wANNOVER tools. No causative mutations were found using Variant Caller and wANNOVER softwares, whereas the “Coverage Analysis” tool revealed a common large deletion in STS gene in a patient with X-linked ichthyosis. Identification of indels in Next Generation Sequencing (NGS) data is a veritable challenge. This study demonstrates the efficacy and effectiveness of using NGS approach to detect large deletions without resorting to specific algorithms for “indel” detection. Our results indicate that the NGS panel is a useful, rapid and cost-effective screening test for patients whose features are suggestive of a genetic etiology involving one of the genes embedded in the panel. It is an excellent alternative to Sanger sequencing as for costs, ease of analysis, and turnaround time.