Background: A genetic background may be responsible for the different clinical courses in sarcoidosis. We analyzed associations between sarcoidosis clinical course and HLA class I/II alleles and susceptibility gene SNPs ANXA11 rs1049550 C/T and BTNL2 rs2076530 G/A in a Portuguese population, investigating possible gene-gene interactions.
Methods: We studied 138 unrelated Caucasian sarcoidosis patients (78 women, 56.5%; mean age, 37.2 ± 12.1 years). Disease that persisted after 2 years was considered chronic. Samples were genotyped for ANXA11 rs1049550 C/T and BTNL2 rs2076530 G/A SNPs using TaqMan Real-Time PCR Assays. HLA class I/II alleles were typed using PCR sequence-specific primers.
Results: Sixty-six patients experienced disease resolution and 72 (52%) developed chronic disease. Comparison of rs1049550 and rs2076530 allele frequencies showed no significant differences. Only the HLA DRB1*03 allele was significantly associated with disease resolution (21.2% vs 4.9% for chronic disease; RR = 0.35; P < .01 after Bonferroni correction). In the logistic regression models evaluating the association between HLA alleles and chronic sarcoidosis adjusted for rs1049550 and rs2076530, only DRB1*03 was significantly associated with disease resolution. No significant interactions were found in any of the logistic regression analyses.
Conclusions: In this population of Caucasian patients with sarcoidosis, only DRB1*03 was associated with disease resolution after 2 years' follow-up, with no significant interactions found for susceptibility gene SNPs ANXA11 rs1049550 or BTNL2 rs2076530.
© 2016 John Wiley & Sons Ltd.