Myostatin, also called as growth differentiating factor 8 (GDF8), a negative regulator of growth in chicken has been characterized at nucleotide and protein level. The total length of the coding frame is 1128 bp encoding 375 amino acids pro-myostatin consisting of first 23 amino acids forming the signal peptide, next 243 amino acids as pre-protein and remaining 109 amino acids forming mature peptide. The protein in dimeric form is biologically active in chicken. This gene harbours many SNPs at promoter, 5’-UTR, exons, introns and 3’-UTR across the breeds of chicken in which coding region had higher level of polymorphism than non-coding regions. The SNPs had significant association with many economic traits such as growth traits, carcass traits, and immune response traits. The body weights of poultry can be rapidly enhanced by knocking down the expression of myostatin gene by RNAi and knocking out the gene by gene-editing, and in one generation more than 26% improvement in body weight was achieved. It is concluded that myostatin has been a promising molecule associated with controlling growth in chicken which may be considered to determine genetic markers for growth and other economically important traits for further use in selection programme, and to improve growth traits rapidly by inhibiting its expression through RNAi and gene editing in poultry.