Research progress in genetic epidemiology of psoriasis in Chinese population

In 1984, the epidemiological survey in China suggested that the prevalence of psoriasis was 0.123 %. By 2008, a survey across six provinces and cities in China showed an increase in prevalence rate to 0.47 %. In comparison, the prevalence in European and American countries ranged from 2% to 4%. Psoriasis is a complex multi-gene genetic disease. In China, 31.26 % of psoriasis patients have a family history. The prevalence of psoriasis among first-degree and second-degree relatives of probands is 7.24% and 0.95%, respectively. The heritability is 67.04% for first-degree relatives and 46.59% for second-degree relatives, showing a trend of decreasing heritability with the increase of genetic coefficient. More than 100 susceptibility gene loci of psoriasis have been identified globally, many of which are associated with immune system-related gene variations. Approximately 38% of these loci are found in the Chinese population. Genetic linkage analysis suggests that the interleukin (IL)-15 gene is a susceptibility gene for psoriasis in Chinese individuals. Genome-Wide Association Studies (GWAS) identified multiple susceptibility gene loci associated with psoriasis. The LOC144817, RUNX1, COG6, and TP63 genes were identified in the multi-center and multi-ethnic meta-analysis. Chinese populations exhibit different allele frequencies in the HLA-I region compared to Western populations. This genetic heterogeneity suggested that different pathogenesis and therapeutic targets might exist across different populations. Researchers found multiple susceptibility loci with specific population effects, which further emphasized the importance of independent research in different populations. With the continuous discovery of susceptibility genes, an important future direction of research will be how to translate these findings into clinical applications, such as personalized treatment and drug development.