Absence oflinkage between idiopathic dilated cardiomyopathy andcandidate genes involved intheimmunefunction ina large Italian pedigree

Idiopathic dilated cardiomyopathy (IDC) isa heartdisease ofunknownaetiology characterised by impairedventricular function usually associated withdilatation ofthecardiac chambers. Inordertotest thehypothesis ofanimmunological cause forthedisease atthegenetic level, we performed linkage analysis betweenthe putative disease locusandsomeofthe potential candidate genesinvolved inthe immuneresponse orcoding forthetargets forautoantibodies in a largemultigeneration family(63members)from southern Italy withautosomal dominant transmission ofthedisease. Twenty-nine polymorphic markers on18different chromosomallocations wereinvestigated, including markerslinked tothegenescoding fortheHLA antigens, theimmunoglobulin heavyandlight chains, thereceptors for theimmunoglobulin Fcfragments, thesubunitsoftheT cellreceptor andtheassociated CD3, CD4, CD8, andCD45antigens, interleukins 1,3,4,5,6,9,and11, theinterleukin 1and2receptors, andthe genescoding fortheP,adrenoreceptor, the adenine nucleotide translocator- 1,andthe cardiac aandPmyosinheavychains. No evidence forgenetic linkage toIDC wasfoundatanyofthesecandidate loci. Theseresults indicate thatthestill unidentified IDCgenemapsoutside several lociinvolved intheregulation ofimmune