Interleukin 17A gene polymorphism rs2275913 is associated with osteitis after the Bacillus Calmette-Guérin vaccination.

Aim: Interleukin-17 (IL-17) appears to promote the host's defence against mycobacterial infections. This study evaluated the association between IL17A gene polymorphism and the risk of Bacillus Calmette-Guérin (BCG) osteitis after newborn vaccination and between IL17A gene polymorphism and IL-17A concentrations in serum.

Methods: IL17A rs2275913 gene polymorphisms and serum IL-17A concentrations were studied in 132 adults aged 21-49 years from across Finland, who had BCG osteitis in infancy after a newborn BCG vaccination. The subjects were recruited in 2007-2008, and their whole-blood samples were sent to the National Institute for Health and Welfare, Turku, Finland. Their genotypes and minor allele frequencies were compared with 405 population-based unvaccinated controls aged two to three months from a prospective birth cohort study.

Results: The genotypes and allele frequencies of IL17A rs2275913 differed significantly between the former BCG osteitis patients and controls. The genotype was variant in 75.8% of cases and 64.0% of controls (p = 0.012), and the minor allele frequency was 50.0% in the cases and 41.6% of the controls (p = 0.009). Serum IL-17 concentrations did not differ significantly between the cases with wild or variant genotypes.

Conclusion: IL17A rs2275913 gene polymorphism was associated with a risk of BCG osteitis after vaccination.