HLA and beta-myosin heavy chain do not influence susceptibility to Chagas'disease cardiomyopathy

An inflammatory dilated cardiomyopathy occurs in 30% of Chagas' disease pat ients, chronically infected by Trypanosoma cruzi, while the remaining infec ted individuals are asymptomatic. Studies have indicated a role for genetic factors in the susceptibility to Chagas' disease cardiomyopathy. In an att empt to identify the genetic factors influencing the development and outcom e of Chagas' cardiomyopathy, we compared the frequencies of alleles from tw o candidate gene loci, class II HLA and a microsatellite marker for the hum an cardiac beta-myosin heavy chain gene in different clinical groups. Patie nts were grouped as asymptomatic or with severe or mild cardiomyopathy. The results indicate that the HLA and myosin microsatellite allele profiles in all cardiomyopathy and in asymptomatic groups are similar. In conclusion, these results establish that polymorphism of HLA-DR and -DQ molecules, as w ell as beta-cardiac myosin, do not influence the susceptibility to differen t clinical forms of Chagas' disease or the progression to severe Chagas' ca rdiomyopathy. On the other hand, male sex was identified as a risk factor f or progression to the more severe forms of cardiomyopathy (relative risk = 8.75). (C) 2000 Editions scientifiques et medicales Elsevier SAS.