Effect of melatonin receptor gene polymorphism in body weight and dimension born local goats

Abstract

Background this study was conducted on a sample of (42) pregnant local goats in the animal field of the Animal Production Department / College of Agriculture / University of Diyala for the period from (12/10/2024) to (10/2/2025). Methods: The study aimed to extract genetic material (DNA), determine the Genotype of the melatonin receptor gene MTNR1A and its relationship to the growth characteristics of mothers and newborns. The polymerase chain reaction (PCR) technique was used, as the results of molecular analysis of the polymerase chain reaction (PCR) product showed the emergence of four genetic variations within Studied  region. The first SNP is T22927C (TT=29, TC=3, CC=4), the second variation is G23011A GG=29), GA=5, AA=2), the third variation is C23195T CT=22), CT=12, TT=2), and the fourth variation is C23195T CT=22, CT=12, TT=2. A23362C (CC=19, AC=14, AA=3).  Results: the results of the current study showed significant differences in the studied variations in the weights of the newborns and the body dimensions of the newborns as well as the mother, where the genetic variation G23011A had a significant difference in the abdominal circumference of the mother, where the genotype AA was superior to the genotypes GG and GA, but as for the weight and length of the mother’s body, the height of the forelock and the height of the rear, as well as the girth heart circumference, there were no significant differences, as for the genetic variations T22927C, (C23195T), and (A23362C), there were no significant differences in the weight and length of the mother’s body, the height of the forelock and the rear, as well as the chest and abdominal circumference. Regarding the birth weaning weight and body dimensions of the newborns Conclusions: The A23362C SNP had a significant effect on chest and abdominal circumferences of the newborns at weaning, with the AC genotype outperforming the CC and AA genotypes. No significant differences were found for the C23195T SNP in terms of birth and weaning weight and body dimensions of the newborn significant differences were found for the A23362C SNP in terms of weaning weight and body dimensions.