TGF-beta1 gene polymorphisms in patients with end-stage heart failure

The regulatory cytokine transforming growth factor (TGF)-beta1 is thought to play a role in atherosclerotic heart disease as well as in idiopathic cardiomyopathy. The production of TGF-beta1 is genetically controlled as polymorphisms in the signaling sequence of the TGF-beta1 gene leucine(10)-->proline and arginine(25)-->proline are involved in the regulation of the protein production level. We investigated whether these polymorphisms are associated with end-stage heart failure caused by dilated cardiomyopathy (CMP) or ischemic heart disease (IHD).

We determined polymorphisms using sequence specific oligonucleotide probing (SSOP) in genomic DNA samples from heart transplant recipients (n = 253) and controls (n = 94). Indications for transplantation were dilated CMP (n = 109) and IHD (n = 144).

We found a difference in TGF-beta1 codon 10 genotype distribution among patients with IHD, dilated CMP, and controls (p = 0.034; chi(2) test). Patients with dilated CMP differed from patients with IHD (p = 0.044) and healthy controls (0.017). The genotype distribution between patients with IHD and controls was comparable. For codon 25, we found no difference in genotype distribution.

The Leu(10)-->Pro (codon 10) polymorphism in the TGF-beta1 gene is associated with end-stage heart failure caused by dilated CMP and not with IHD. This observation suggests that TGF-beta1 is involved in the pathogenesis of CMP.