Clc genomics workbench screenshot1/13/2024 Examples include intellectual disability, deafness, familial cardiomyopathy and retinitis pigmentosa. Common disorders evaluated by clinical geneticists are caused by heterogeneous Mendelian loci and lend themselves to enrichment strategies followed by NGS. NGS could be particularly advantageous in research and testing for genetically heterogeneous hereditary conditions. Additionally, NGS provides entirely new research and diagnostic capabilities, including whole genome screening for novel mutations and sequencing biological specimens for the genomic signature of novel infectious agents. It is predicted that in the near future NGS might replace array based techniques and Sanger sequencing in their current clinical applications for the detection of mutations. With the high throughput and decreased sequencing costs achieved by NGS, it is no longer impossible to sequence hundreds or even thousands of exons and other genomic sequences in an individual with a suspected genetic disease. The advent of NGS technologies is expected to transform the practice of medical genetics. The goal of our study was to evaluate the capacity of array based sequence capture target enrichment (SCE) and massively parallel, next generation sequencing (NGS) to successfully identify mutations in candidate genes for the developmental ocular birth defects anophthlmia, microphthalmia and coloboma. Although improvements will be necessary in accuracy, speed, ease of data analysis and cost, our study confirms that NGS can be used in research and diagnostic settings to screen for mutations in hundreds of loci in genetically heterogeneous human diseases. Different approaches were evaluated for distinguishing false positives (sequencing errors) and benign polymorphisms from potentially pathogenic sequence changes that require further follow-up. A deletion of one base in a long polyG stretch (c.77delG) was not registered initially by the GS Reference Mapper, but was detected in repeated analysis using two different software packages. The nucleotide substitution c.527G>C was easily identified by NGS. These changes were a c.527G>C (S176T) substitution and a single basepair deletion c.77delG. We assayed two samples with heterozygous sequence changes in PAX2 that were previously identified by conventional Sanger sequencing. Our study assessed whether array based target enrichment followed by re-sequencing on the Roche Genome Sequencer FLX (GS FLX) system could be used for novel mutation identification in more than 1000 exons representing 100 candidate genes for ocular birth defects, and as a control, whether these methods could detect two known mutations in the PAX2 gene. Sequence capture enrichment (SCE) strategies and massively parallel next generation sequencing (NGS) are expected to increase the rate of gene discovery for genetically heterogeneous hereditary diseases, but at present, there are very few examples of successful application of these technologic advances in translational research and clinical testing.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |