To investigate the association of polymorphisms of the SSA1 gene (OMIM 109092) with primary Sjögren's syndrome (SS) and anti-SS-A/Ro52 antibody production.
Polymorphisms of SSA1 gene in 111 Japanese SS patients and in 97 healthy controls were analyzed with polymerase chain reaction and automated DNA sequencing.
A new single-nucleotide polymorphism (SNP) was identified in intron 1 at position 7216. The allele frequency and genotype of 7216A/G were not significantly different between SS patients and control subjects. However, the allele frequency and genotype of 7216A/G were associated with the presence of anti-SS-A/Ro52 antibody among primary SS patients. The association was not found in patients with SLE, suggesting the limited role for the SNP in anti-SS-A/Ro52 antibody production. The 9571C/T polymorphism, which has been shown to associate with anti-SS-A/Ro52 antibody in Caucasian patients, was not associated with the presence of anti-SS-A/Ro52 antibody in Japanese patients.
7216A/G polymorphism of SSA1 gene may be one of the genetic factors that determine the presence of anti-SS-A/Ro52 antibody in patients with primary SS.