Association of Polymorphisms of Exon 2 of Transcription Factor 7 Gene with Fat Traits of Blood and Fat Tail in Lori-Bakhtiari and Zel Sheep Breeds

Transcription factor 7 gene (TCF7) is located on genomic candidate region for fat traits on sheep chromosome no. 5 and it is excepted to affect fat traits. In the present study, blood samples were collected from 164 Lori-Bakhtiari sheep in Shouli breeding station located at Shahr-e-Kord city, and 113 Zel sheep in Shirang breeding station located at Gorgan city. DNA was extracted from blood samples using modified salting out method and polymerase chain reactions were performed for amplification of 643 bp fragment of exon 2 of locous TCF7 gene. Determination of genotype patterns of sheep were obtained according to result of vertical electrophoresis and AA, AB and BB genotypes were revealed. In Zel breed, AA and AB genotype patterns were observed with frequency of 71 and 29 percent respectively and in Lori-bakhtiari breed, AB and BB genotype patterns were observed with frequency of 10 and 90 percent. There was no significant effect of genotype patterns on fat traits In Zel breed but it was significant effect in Lori-Bakhtiari breed. AB genotype had the greatest impact on fat-tail weight and blood cholesterol and BB genotype had considerable effect on blood triglycerides.