HLA and immunoglobulin polymorphisms in idiopathic dilated cardiomyopathy.
Dilated cardiomyopathy (DCM) is an idiopathic heart muscle disorder. The presence of circulating cardiac antibodies and the association with HLA-DR4 are consistent with autoimmune pathogenesis in a subset of patients. Sixty-eight DCM patients and 277 controls were typed for IgG heavy-chain constant region (Gm) and kappa light-chain (Km) allotypes. All patients and 210 of the 277 controls were HLA-DR typed. The Gm (1, 3, 17; 23; 5*, 21, 28) phenotype was overrepresented in DCM compared with controls (25% vs 13%, p = 0.0139, pc = NS, RR = 2.23). The frequency of this phenotype was higher in patients with younger age at onset, shorter symptom duration, and among those who were positive for cardiac as well as for non-organ-specific autoantibodies than in controls. A higher frequency of the Gm (1, +/- 2, 3, 17; +/- 23; 5*, 21, 28) heterozygous phenotypes was also found in DCM compared to controls (40.91% vs 26.89%; p = 0.02, pc = 0.04, RR = 1.88). The finding of Gm heterozygosity in DCM was associated with serum positivity for cardiac antibodies. A higher proportion of DCM patients were positive for both the Gm (1, 3, 17; 23; 5*, 21, 28) phenotype and HLA-DR4 compared to normals (3/68 vs 0/210; p = 0.04, RR = 22.50).(ABSTRACT TRUNCATED AT 250 WORDS)
Martinetti
M
M
Immunohematology and Transfusion Center, Pavia, Italy.
Dugoujon
J M
JM
Caforio
A L
AL
Schwarz
G
G
Gavazzi
A
A
Graziano
G
G
Arbustini
E
E
Lorini
R
R
McKenna
W J
WJ
Bottazzo
G F
GF
D000328:Adult; D001323:Autoantibodies / Q000032:analysis; D002311:Cardiomyopathy, Dilated / Q000276:immunology*; D004198:Disease Susceptibility; D005260:Female; D005787:Gene Frequency; D005819:Genetic Markers; D006680:HLA Antigens / Q000235:genetics*; D006801:Humans; D007074:Immunoglobulin G / Q000235:genetics; D007145:Immunoglobulin kappa-Chains / Q000235:genetics; D007136:Immunoglobulins / Q000235:genetics*; D016130:Immunophenotyping; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic
D001323:Autoantibodies; D005819:Genetic Markers; D006680:HLA Antigens; D007074:Immunoglobulin G; D007145:Immunoglobulin kappa-Chains; D007136:Immunoglobulins