Prevalence of IL12B rs3212227 Polymorphism in Patients With Plaque Psoriasis From Guatemala 2310585

Abstract Introduction Psoriasis is an immune-mediated and inflammatory disease in which the IL-12/IL-23 axis plays a key role. The IL12B gene encodes the p40 subunit shared by both cytokines and has been implicated in the differentiation of Th1 and Th17. The single nucleotide polymorphism rs3212227 in IL12B has been associated with psoriasis and psoriatic arthritis in Caucasian populations, with inconsistent findings in Hispanic populations. No prior studies have described the prevalence of this polymorphism in Guatemalan patients with psoriasis. Methods An observational and descriptive study was conducted in adult patients with plaque psoriasis attending a tertiary referral center in Guatemala. Clinical data were collected, including disease severity assessed by PASI and evaluation for psoriatic arthritis using CASPAR criteria. Genomic DNA was extracted from peripheral blood samples. The rs3212227 polymorphism was identified using polymerase chain reaction followed by Sanger sequencing. Descriptive statistics were used to summarize clinical characteristics and genotype and allele frequencies. Exploratory analyses were performed to assess relationships between genotype and clinical variables. Results Thirty-five patients were enrolled, of whom nine yielded sequencing of sufficient quality for genotyping. Genotype frequencies were 88.9% for TT and 11.1% for GG, with a G allele frequency of 11.1%. The mean PASI score was 13.3 ± 8.4. Twelve patients met criteria for psoriatic arthritis. No statistically significant associations were observed between the rs3212227 genotype and clinical variables. Conclusion In this cohort of Guatemalan patients with plaque psoriasis, the IL12B rs3212227 polymorphism was infrequent. Although limited sequencing yield restricted genotype-phenotype analysis, the detection of the G allele confirms its presence in the Guatemalan population and supports the need for larger studies to further characterize IL12B polymorphism in psoriasis within Central America. Funding Source Universidad Francisco Marroquín (partial institutional support for molecular biology consumables) Topic Categories Immune Mechanisms of Human Disease (HUM)