Results of a new study from England provide additional evidence supporting the existence of shared genetic characteristics between psoriasis and psoriatic arthritis.
However, the findings also reveal insights into the genetics of psoriatic arthritis that help to explain fundamental differences between the two conditions.
John Bowes, PhD, research associate at The University of Manchester, Manchester, UK, and colleagues recently published the research in Nature Communications.
“This study demonstrates substantial allele sharing at previously reported psoriasis susceptibility loci as would be expected given the shared clinical characteristics,” the study authors wrote. “In addition, the study reveals key insights into the genetics of psoriatic arthritis (PsA) that begin to explain fundamental differences between psoriasis and PsA.”
The case-control association study included 1,962 patients with PsA and 8,923 controls using the Immunochip (Illumina), a custom genotyping array. The gene identified by the research team lies on chromosome 5 and is not the first PsA-specific gene to be identified. Patients who carry the HLA-B27 gene are also more likely to develop PsA.
In addition, the findings highlight that CD8+ cells could be the key drivers of inflammation in PsA, according to the investigators.
“Identifying disease-specific genetic risk factors has important implications for epidemiology and pharmacogenetics as it may allow the stratification of patients with psoriasis to identify those at high risk of developing PsA and potentially identify new therapeutic targets,” wrote the researchers.