An Association Study On Single Nucleotide Polymorphisms In 9q33-34 With Psoriasis In Chinese Han Population

Background Psoriasis (psoriasis, PS, OMIM#177900) is a common inflammation cutaneous disorder characterized by red scaly patches and abnormal epidermal proliferation with a prevalence of 1-5% in general population and 0.123% in Chinese population. The incidence of this disease around the world is different. The incidence rate of the Caucasian population is 2～5% ,that of the population in Asia is 0.1～0.3%, and in Chinese the incidence rate is about 0.12%. Clinically, psoriasis vulgaris (psoriasis vulgaris, PsV) is the most common, accounting for the total number of patients over 90%. The exact pathogenesis of psoriasis remains unclear. It is agreed generally that the psoriasis is a complex disease which arises from genetic and environmental factors. To date, Online Mendelian Inheritance in Man Several psoriasis susceptibility loci have been mapped : PSORS1 on 6p21.3, PSORS2 on 17q, PSORS3 on 4q, PSORS4 on 1cen-q21, PSORS5 on 3q21, PSORS6 on 19p, PSORS7 on 1p, PSORS8 on 16q, PSORS9 on 4q31, PSORS10 on 18p11 , and PSORS11 on 5q31.1-q33.1. In addition, a large number of domestic and foreign linkage and association analysis studies have further identified CCHCR1, HLA-C, HCG27, POU5F1, TCF19,CDSN, IL12B, IL23R, IL15, IL20 and so on , predisposing genes of psoriasis or genetic susceptibility variants for psoriasis in these regions.In 2002, our group performed a genome a genome-wide linkage scan in 61 Chinese Han families with psoriasis and found suggestive evidence for linkage on 9q33.In 2005, Sun carried out a fine mapping on 9q33-34 in 160 Chinese Han families with psoriasis and further confirmed that 9q33-34 is a susceptibility loci in Chinese Han. Recently, our group performed Genome-wide association study studied in psoriasis of Chinese Han and found that some SNPs of this region were associated with psoriasis susceptibility psoriasis in Illumina 610k genotype data.Objective To study the relationship between eight single nucleotide polymorphisms of 9q33-34 and psoriasis susceptibility in Chinese Han population.Methods Based on the previous results of genome wide association study, the genotyping of 8 SNPs in 9q33-34 in 1,103 cases of psoriasis and 1,104 controls was done by using Sequenom MassArray system. Statistical analysis was performed by the Plink 1.03 software.Results There were no significant differences in allele frequencies of the eight SNPs between cases and controls (P >0.05).Conclusion It suggested that eight SNPs in 9q33-34 could not relate to psoriasis susceptibility in Chinese Han population.