Follistatin gene is a member of transforming growth factor –β super family involved in muscle growth. The present study was carried out to characterize the nucleotide variability in the exonic (coding) region of FSTN gene in boiler (PD-1) line and control layer chicken lines. A PCR product of 219 bp of exon-3 was amplifi ed and nucleotide variability was studied using PCR-SSCP technique. The PCR products were sequenced to confi rm the variability in coding sequence. The present study revealed that the exon3 sequence of FSTN gene was monomorphic having similar sequence pattern in all individuals. Growth data was also analyzed, the growth performance of male and female differed signifi cantly at six week of age. It is concluded that exon3 of FSTN gene was monomorphic without showing any variation in the nucleotide composition both in broiler and layer chicken lines. The codon did not show any effect on variation in growth traits in chicken