HLA, autoimmunity, and rheumatic heart disease. Apparent or real associations?

T he report of Ozkan et all in this issue of Circulation identifies HLA allelic associations with rheumatic heart disease (RHD) in a Turkish population, a population previously untested for HLA associations with RHD. Of interest, they report a significantly increased expression of B16, DR3, and DR7 in their patient sample. The increased expression of DR3 and DR7 alleles observed in their patients supports other reports of similar associations with RHD2,3 and adds to a growing overall compilation of purported class II associations with RHD,2-5 including DR1,4 DR2,5 DR4,6 DRw6,4 and DQw2.2 Decreased expression among patients for DR5 was also found in their study; likewise, decreased allelic expression among patients for DRw6,6 DR5,2 DR8,5 and DR22 has been reported elsewhere.