eng Rovedar Journal of World’s Poultry Science 2980-7999 2025-03-25 4 1 1 7 10.58803/jwps.v4i1.63 65 Kusnadidi Subekti 0 https://orcid.org/0000-0001-5843-3456 Nada Iswari Samara 1 https://orcid.org/0009-0008-0052-2649 Firda Arlina 1 https://orcid.org/0000-0001-7141-6431 Department of Science Technology of Livestock Production, Faculty of Animal Science, Andalas University, Indonesia Departement of Science Technology of Livestock Production, Faculty of Animal Science, Andalas University, Indonesia Introduction: Pitalah ducks are one of Indonesia's local genetic resources that can be utilized to develop quality livestock products. The present study aimed to identify the diversity of the Myostatin gene (MSTN/HaeIII) exon-3 in Pitalah ducks, a local duck breed from West Sumatra, Indonesia. Materials and methods: The present study utilized 40 samples of DNA from the blood of Pitalah ducks (11 males and 29 females, with an average body weight of 1,450 g and an average age of 12 months) that were intensively reared at the Andalas University animal husbandry unit in Indonesia. DNA from blood samples was isolated using the genomic DNA Extraction Kit. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) was used as the method. The isolated DNA was then amplified using a primer that produced a 438 bp fragment of the MSTN gene. The amplification product was restricted using the HaeIII enzyme, which recognizes the cutting site at GG↓CC. Results: Based on the findings of 40 samples, 65% of homozygous truncated genotypes (+/+), 35% heterozygous genotypes (+/-), and no homozygous untruncated genotypes (-/-) were found. Based on the current results, two genotypes were identified. The current findings indicated genetic diversity, as the frequency of each allele exceeds 1%. The allele frequency (+) was 0.825, the allele (-) was 0.175, and the observed heterozygosity was greater than the expected heterozygosity. Conclusion: The allele frequency of the MSTN/HaeIII exon-3 gene in Pitalah ducks is polymorphic (diverse) within the Pitalah duck population. Genotype frequencies of the MSTN/HaeIII exon-3 gene are in Hardy-Weinberg equilibrium. https://jwps.rovedar.com/index.php/JWPS/article/view/63 HaeIII Enzyme Myostatin gene Pitalah duck Polymorphism