Next Generation Exome Sequencing of paediatric Asthma Identifies Rare and Novel Variants in Candidate Genes

Abstract

Background: Multiple genes have been implicated to have a role in asthma predisposition by association studies. Paediatric patients often manifest more extensive disease and a particularly severe disease course. It is likely that genetic predisposition could play a more substantial role in this group. This study aims to identify the spectrum of rare and novel variation in known paediatric asthma susceptibility genes using whole exome sequencing-analysis in nine individual cases of childhood onset allergic asthma. Data were processed through an analytical pipeline to align sequence reads, conduct quality checks, identify and annotate variants where patient sequence differed from the reference sequence. Results: DNA samples from the nine children with a history of bronchial asthma diagnosis underwent targeted exome capture and sequencing. For each patient, the entire complement of rare variation within strongly associated candidate genes was catalogued. The analysis showed 21 variants in the subjects, 13 had been previously identified and 8 were novel. Also, amongst of which, nineteen were non-synonymous and 2 were nonsense. With regard to the novel variants, the 2 non-synonymous variants in the PRKG1 gene (PRKG1: p.C519W and PRKG1: p.G520W) were presented in 4 cases, and a non-synonymous variant in the MAVS gene (MAVS: p.A45V) was identified in 3 cases. The variants we found in this study will enrich the variants spectrum and build up the database in the Saudi population. Novel eight variants were identified in the study which provides more evidence in the genetic susceptibility in asthma among Saudi children.Conclusion: Screening a cohort of Saudi children for molecular identification of polymorphisms associated with allergic asthmatic response. These, together with the clinical phenotypes, revealed genetic determinants for paediatric asthma and also we compared to the similar previous reports. Providing a genetic screening map for the molecular genetic determinants of allergic disease in Saudi children, with the goal of reducing the impact of chronic diseases on the health and the economy. We belief that the advanced specified statistical filtration/annotation programs used in this study succeeded to release such results in preliminary study, exploring the genetic map of that disease in Saudi children.