Candidate Gene Expression and SNP Analyses of Toxin-Induced Dilated Cardiomyopathy in the Turkey(Meleagris gallopavo)

Dilated cardiomyopathy (DCM), a heart disease, affects many vertebrates including humans and poultry. The disease can be either idiopathic (IDCM) or toxin-induced. Idiopathic DCM often occurs without a consensus cause. Though genetic and other studies of IDCM are extensive, the specific etiology of toxin-induced is still unknown. Here, our objective was to compare the level of mRNA expression of two candidate genes including troponin T (cTnT) and phospholamban (PLN) using quantitative reverse transcription polymerase chain reaction (RT-PCR) in toxin-induced DCM affected and unaffected turkeys. Cardiac TnT and PLN were chosen because their spontaneous expression has been reported to be associated with IDCM. We also scanned these genes for single nucleotide polymorphisms (SNPs) that could be useful in evaluating their functions in the incidence and severity of toxin-induced DCM in turkeys. There were no significant differences between affected and unaffected birds in the expression of both cTnT and PLN. A total of 12 SNPs were detected in cTnT and PLN DNA sequences. One of the seven haplotypes detected in cTnT was the most frequent. Linkage analysis showed that cTnT gene was unlinked on the current turkey genetic map. Resources developed here, including SNPs, haplotypes, cDNA sequences, and the PCR-RFLP genotype procedure will be used for future investigations involving cTnT and PLN and toxin-induced DCM.