Study on genetic structure of CAST gene by PCR- SSCP method and its association with growth traits in lori-Bakhtiari sheep breed

In this study, a 254 bp fragment containing exon 6 and a part of introns 5 and 6 of ovine CAST gene were amplified in 169 Lori-Bakhtiari lamb from Lori -Bakhtiari sheep breeding station by polymerase chain reactions. The PCR-SSCP method and vertical electrophoresis of PCR products on 12% acrylamide gel at 4 C° and silver-staining were used for genotyping of amplified fragments. Ten genotypic patterns containing AA, BB, AB, AC, AD, BE, AF, AG, AH and AJ were identified with frequencies of 0.029, 0.195, 0.065, 0.166, 0.024, 0.08, 0.325, 0.053, 0.012 and 0.042, respectively. Association analysis with growth traits demonstrated different genotypes significantly associated with birth weight, weaning weight and daily gain from birth to weaning (P<0.05). The best genotypes for birth weight were AB and AC and for weaning weight and daily gain were AJ and AB. It seems that sequencing of this gene and identification of probable SNPs in the next projects and also association studies at larger population, can determine favorable alleles and genotypes of CAST gene for growth traits with very high accuracy and use them in Marker Assisted Selection (MAS).