This study assessed exon 1 sequence variants in both genes and investigated their associations with growth traits in Saanen and Alpine goats. Sequencing identified an MSTN exon 1 c.163C>G polymorphism causing a missense substitution (Leu→Val) at the 15^th position of the protein (p.Leu15Val). In contrast, Myf5 exon 1 exhibited a c.232T>C variant representing a synonymous (silent) change of the Phe residue at the 32^nd position of myogenic factor 5 (p.Phe32=). In Alpine goats, the Myf5 p.Phe32= SNP was significantly associated with chest girth (P=0.011), with the TC genotype exhibiting the highest mean value. In Saanen goats, the same Myf5 silent SNP was significantly associated with chest width (P=0.028), again with TC showing the highest mean. For the MSTN p.Leu15Val SNP, Alpine goats displayed a significant association with body weight (P=0.042), with the CC genotype having higher body weight than CG and GG. In Saanen goats, the MSTN missense variant was significantly associated with body length (P=0.031), with the CC genotype showing the highest means. While in-silico tools collectively suggested non-deleterious effects of p.Leu15Val on protein structure, function, and stability, molecular docking of MSTN with its receptor indicated greater contributions of residues in the altered protein compared with the wild-type form. Given the negative effect of MSTN on muscle cell development, the computational analyses indicated that this missense mutation further supports binding with the receptor in the altered genotypes. Due to this more compact interaction, increased negative regulation of muscle cell development is expected in individuals with the altered genotypes.

To Cite This Article: Durmuş M, 2026. Assessment of Myf5 and MSTN genetic variants as predictors of growth traits in saanen and alpine goats. Pak Vet J, 46(3): 564-574. http://dx.doi.org/10.29261/pakvetj/2026.045