Association Study On Atopic Dermatitis Susceptibility Loci In Chinese Han Population

Background: Atopic dermatitis (AD) is a chronic, relapsing form of inflammatory skindisorder affected by genetic and environmental factors. Recent Genome-wideassociation studies(GWAS) for AD and a meta-analysis of GWAS have identifiedseveral genetic locus that predispose carrier to AD in European and Japanesepopulations. To date, it is unclear whether these novel susceptibility loci are associatedwith Chinese Han AD patients, and the importance of replication in different populationshould not be overlooked.Objective: The aim of the current study was to investigate association of10confirmedand suggestive AD susceptibility loci with AD, and further explore the relationships ofthese locus with AD phenotypes in a large Chinese Han cohort.Methods: We recruited2,205AD patients and2,116healthy controls in Chinese Hanpopulation. The SNPs were genotyped using the Sequenom MassArrayTMiPLEX Goldplatform. Data were analyzed with PLINK1.07software and SPSS13.0.Results: All of the17SNPs genotyped were in HWE (P>0.05) in all subsets，except forrs7637099and rs6461923.(1) The rest of15SNPs showed no statistically significantfor AD after Bonferroni Multiple Testing correction.(2) The frequency of variant Callele of rs878860was significantly different between the early-onset (＜1year) andlate-onset cases (≥1year)(62.3%vs.57.9%, P=0.042, OR=1.20), and the distributionof genotypes for rs878860revealed significant differences between the two groups(P=0.042).(3) The frequency of rs7927894variant T allele was preferentially higherin.patients with a family history of atopy than those without (19.4%vs.16.7%, P=0.031,OR=1.201), and the distribution of genotypes for rs7927894showed significantlydifferent between the two groups (P=0.031).(4) The frequency of rs952599variant Tallele was significantly higher in.AD with concomitant bronchial asthma and allergicrhinitis compared to “pure” AD (64.9%vs.58.6%, P=0.047, OR=1.31), and the distribution of genotypes for rs952599was significant differences between the twogroups (P=0.046).(5) The C allele of rs6780220was preferentially higher in patientswith keratosis pilaris than.to those without (61.4%vs.55.8%, P=0.01, OR=1.26), andthe distribution of genotypes for rs2066808showed a statistically significant betweenthe two groups (P=0.042).(6) The frequency of rs2164983variant C allele of wassignificantly higher in AD with the.elevated total IgE compared to those with normaltotal IgE (90.3%vs.86.3%, P=0.022, OR=1.49), and the distribution of genotypes forrs2164983revealed significant differences between the groups (P=0.015). There was nosignificant association for any other clinical features of AD for the other SNPs (P>0.05).Conclusions:(1) Our negative findings suggested that the10susceptibility locus,previously reported by European and Japanese populations, are not implicated in thedevelopment of AD in Chinese Han population.(2) rs878860within11p15.4may berelated to the early age of onset of AD.(3) rs7927894within11p13.5might associatewith AD with a family history of atopy.(4) rs952559within8p21.13may relate to thedevelopment of AD with concomitant bronchial asthma and allergic rhinitis.(5)rs6780220within3p21.33might associate with AD with keratosis.(6) rs2164983within19p13.2might relate to AD with elevated total IgE. Therefore, we might indicatethat sub-phenotypes of AD are caused by specific genetic components. This study maythrow novel insights into the genetic pathogenesis of AD and be helpful for us to gain abetter understanding on disease pathogenesis and clinical evaluation.