Haplotype Structure and Variation of Telomerase reverse Transcriptase (tur TERT) Gene in Turkeys(Meleagris Gallopavo)

Abstract

Abstract: Telomerase is a specialized ribonucleoprotein enzyme complex that adds telomere repeats (5’-TTAGGG-3’) to the end of chromosomes. Mutations in telomerase reverse transcriptase (TERT) gene leads malfunction of telomerase enzyme which causes short telomeres and associated with age-related diseases. A total DNA sequence of 28 kb including the turTERT gene was screened by re-sequencing for structural variation based on single nucleotide polymorphisms (SNPs) and haplotypes using a diversity panel of turkeys. Seven SNPs, including four and three SNPs were identified in the introns 7 and 8 respectively. The minor alleles ranged in frequency from 0.05 to 0.30 with the observed heterozygosity from 0.09 to 0.42.Most of the SNPs did not follow the Hardy Weinberg Equilibrium (P<0.05). Linkage disequilibrium among the SNPs ranged from 0.46 to 1.00. A total of 15 haplotypes were identified and assembled into 4 haplogroups. The haplogroups frequencies ranged from 0.10 to 0.38 in the diversity panel of turkeys. The most frequent haplogroup was turTERTHap3 with a frequency of 0.38. Of the haplogroups, Royal Palm had a unique haplogroup of turTERTHap1 as expected while most of Commercial, Bourbon Red, Blue Slate and Spanish Black birds had another unique haplogroup of turTERTHap4. Most of wild turkeys were laid within the haplogroup of turTERTHap3. The haplotype groupings of TERT gene variations of turkeys confirmed that Royal Palm and wild turkey birds possess unique genetic groups.The genomic reagents gathered in the present study will be useful for future genotype: phenotype evaluation studies between turTERTand traits in the turkey using a candidate gene approach