The frequency of serum amyloid A2 alleles in the Japanese population.

The incidence of serum amyloid A2 alleles (SAA2 alpha and SAA 2 beta) in the Japanese population was analyzed by PCR-RFLP analysis. The SAA2 alpha allele was predominant (approximately 90%) in both healthy controls and adult patients with rheumatoid arthritis. There was no significant association of allele patterns with AA amyloidosis in the patient group. These results are discussed in comparison with those of previous reports from other areas.