Abstract:
Circadian clock genes including Cryptochrome-1 are involved in the molecular mechanism of the biological clock which controls the behavioral, physiological and biochemical circadian rhythms of animals. The turkey Cryptochrome1 (turCry1) gene for DNA sequence variations was screened and evaluated the relationships among haplogroups with the performance traits. DNA sequences of turCry1 (15.0 kb) gene were screened using a total of 290 turkey birds by sequencing of the individual amplicons. In the turCry1 gene, seven SNPs including four and three in the introns 3 and 6 were identified, respectively. The D´ among SNPs ranged from 0.48 to 0.89. The pairwise FST ranged from 0.004 to 0.67 among turkey birds. Haplotypes observed from the 7 SNPs were grouped into seven haplogroups with the frequencies ranging from 0.02 to 0.96, were significantly associated with average daily gain (ADG) for the period of 35 - 68 days, feed conversion ratio (FCR) for the periods of 160 - 231 days and 34 - 231 days, egg production and ejaculate volume (p≤0.05). DNA sequence variations of the turCry1 gene may have some regulatory role in the molecular mechanism of the circadian clock which may affect the overall mechanism of the circadian clock. The turCry1 is a good candidate gene for association studies in turkey. In general, these data support our hypothesis that DNA sequence variations of clock genes at the nucleotide and haplotype levels are associated with the differences in performance traits. In conclusion, the reported genomic information in the present study would be valuable for future genotype-phenotype evaluation studies between turCry1gene and other traits in the turkey using candidate gene approach.
