LINKAGE OF MYOSTATIN GENE POLYMORPHISMS WITH CARCASS PARAMETERS AND EFFECTS OF AMINO ACID CHANGE ON PROTEIN FUNCTION OF BROILER CHICKENS

This experiment was designed to assess the association of Myostatin gene exon 1 polymorphisms with carcass parameters and determine the effect of amino acid change on protein function of four commercial broilers; Arbor Acre, Arbor Acre Plus Cobb and Ross. Two-hundred-day-old chicks of mixed sexes were randomly assigned into five equal-sized cells, each containing forty birds with ten birds per strain. The carcass characteristics considered were eviscerated weight, breast weight and thigh weight. At 12^th week, blood samples were collected via brachial vein of forty birds for DNA extraction. Amplicons were visualized on 1% agarose gel. The amplified products were sequenced and single nucleotide polymorphisms were identified using codon code aligner. The results revealed twenty-seven polymorphisms comprising of twenty-two transition and five transversion mutations. Polymorphisms within exon 1 of the Myostatin gene significantly (P<0.05) associated with carcass parameters in the four commercial broilers. In conclusion, Arbor Acre birds with adenine and thymine alleles should be selected and reared for meat. Cobb and Arbor Acre Plus with adenine allele should be considered while birds possessing adenine and guanine alleles in Ross should be selected and raised for meat production. Non-synonymous substitution in exon 1 such as proline to arginine may possibly influence growth and skeletal muscle development in the population by enhancing nutrient delivery to muscles. Mutation changing from threonine to histidine may influence muscle growth because histidine is essential for muscle growth. Mutation of aspartic acid changing to arginine in is a missense mutation, which disrupts function of Myostatin leading to increased carcass weight, muscle growth and development. Therefore, Ross can be recommended having higher Myostatin adenine and guanine alleles with non-synonymous mutation of aspartic acid to arginine which displayed superior carcass parameters confirmed suitability for high-yield meat production.