Association Analysis Between SYNE2 Gene And Clinical Phenotypes Of Psoriasis Vulgaris In Han Chinese Population

Background Psoriasis vulgaris(PV) is a chronic relapsing inflammatory skin diseases and characterised by red plaque and thick scale. The incidence of psoriasis around the world is about 0.91~8.50%, and the incidence of psoriasis in China is rising. The exact mechanism of psoriasis is still unclear. It is accepted that psoriasis is related with the interaction of genetic factor, immunity and environment. Presently, psoriasis is regarded as an skin autoimmune disease, mediated by T cells, characterised by histopathological changes like hyperkeratosis and parakeratosis. Recently, our team identified 16 SNPs within 15 new genes/loci associated with psoriasis by a large-scale whole exome array analysis. Based on this, we can reveal the etiology and pathogenesis of PV with the help of genotype-phenotype studies.Objective By the stratifying analysis of psoriasis clinical phenotypes, such as age of onset(early onset/ later onset), family history(positive/ negative), clinical types(guttate cases/plaque cases) and severity(mild cases/moderate cases/severe cases), we performed a association study, to explore the correlation between SYNE2 gene rs2781377 polymorphism and clinical phenotypes of psoriasis vulgaris in Chinese Han population. It will be help for the explanation of the PV mechanism.Methods 16786 unrelated cases and 22920 unrelated controls were recruited. The clinical information is collected by the same structured questionnaire. Genotype data of the SYNE2(rs2781377) is obtained from our previous large-scale whole exome array analysis. The association between SNPs and phenotypes of psoriasis were performed using Chi square test with SPSS19.0. Finally, the P-value, odds ratio(OR) and 95% confidence interval(95%CI) were calculated for all these analyses.Results 1. The frequencies distribution of alleles(x2 = 63.70,P = 1.45E-15,OR = 0.83,95% CI = 0.79-0.87) and genotypes(AA: x2 = 21.53,P=3.48E-06, OR=0.63,95% CI =0.51-0.76; AG: x2 = 45.24, P=1.74E-11, OR=0.84, 95% CI =0.79-0.88) for SYNE2(rs2781377) presented statistical difference between the cases and controls.2. Stratifying analysis was made according to psoriasis clinical phenotypes, like age of onset, family history, clinical types and severity. The frequencies distribution of alleles presented statistical difference between the cases and later onset cases( x2 = 4.32,P=3.77E-02,OR=1.11,CI =1.01-1.22). Stratified analyses showed that the frequencies distribution of alleles of rs2781377 polymorphism was associated with early onset psoriasis cases. However, there were no statistical difference between rs2781377 polymorphism within SYNE2 gene and clinical phenotypes such as family history(positive/ negative), clinical types(guttate cases/plaque cases) and severity(mild cases/moderate cases/severe cases).Conclusions The findings indicate the rs2781377 polymorphism within SYNE2 gene is significantly correlated with psoriasis vulgaris, especially with early onset psoriasis cases, but is not associated with some clinical phenotypes including family history, clinical types and severity in Chinese Han population.