Attempted Replication of 50 Reported Asthma Risk Genes Identifies a SNP in RAD50 as Associated with Childhood Atopic Asthma

Department of Epidemiology and Public Health, Yale University School of Public Health, New Haven, Conn., USA.
Human Heredity (Impact Factor: 1.47). 07/2011; 71(2):97-105. DOI: 10.1159/000319536
Source: PubMed


Asthma is a childhood disease that is strongly influenced by genetic factors. We sought to replicate an association between single nucleotide polymorphisms (SNPs) of the top-ranked candidate genes and childhood atopic asthma in Perinatal Risk of Asthma in Infants of Asthmatic Mothers (PRAM) study subjects.
Using data from a systematic literature search and an exploratory genome-wide association study conducted in a subset of the PRAM cohort, we followed a strict procedure to generate a ranked list of candidate genes. SNPs in the top 50 genes were genotyped in the full PRAM cohort (n = 103 cases with doc- tor-diagnosed atopic asthma at age 6, and n = 499 controls).
The literature search identified 251 prior risk genes from 469 publications. RAD50 (rs2706347) and PTPRE (rs10830196) revealed crude associations with asthma at a Bonferroni-corrected level of significance (p < 0.0011). IL4R (rs1801275), CCL5 (rs2280788), and TBXA2R (rs4523) revealed nominal significance (p < 0.05). When adjusted for race and gender, only rs2706347 in RAD50 remained significantly associated with asthma. SNPs in frequently replicated asthma risk genes, including TNF, IL13, ADAM33, TGFB1, and MS4A2, revealed no association.
RAD50 may be a promising candidate asthma risk gene. Lack of evidence of highly reported polymorphisms in the present study highlights the genetic heterogeneity of asthma and emphasizes the need for robust replication of candidate genes.

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    • "We previously identified 251 asthma candidate genes from the literature [23]. We queried the list of 38,103 variants that passed the QC filters to identify those variants that were annotated as being within or near one of these genes. "
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    Full-text · Article · Jun 2012 · The Journals of Gerontology Series A Biological Sciences and Medical Sciences
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