摘要：Myostatin (MSTN) gene plays a key role in skletal muscle homeostasis such as inducing muscle athrophy, poliferation of myoblast, increasing ubiquitin-proteasomal, downregulating IGF pathway, and glucolysis. Myostatin gene expression is controled by CpG island located in promoter region. The objectives of this research were to identify polymorphism of MSTN promoter gene and to associate the polymorphism of SNP with growth and muscling traits in Bali cattle. A total of 48 Bali cattle from BPTU-HMT Bali island was screened to identify genetic polymorphisms in MSTN promoter region using sequencing method. The growth and muscling traits were measured at 12 months of age. The muscling traits were evaluated using ultrasound console with linear transducer having frequency 6.5 Hz and scaning we conducted at 130 mm in deep. Analysis of polymorphism was conducted by using PopGen 1.32 software. The association of MSTN with growth and muscling traits were analyzed by using General Linear Model (GLM) procedure. This result showed that a total of 20 polymorphic SNPs (seven SNPs in CpG island) were detected in this region. Although, only 3 SNPs (g.-8078C>T, g.-7996G>C, and g.-7930A>G) had equilibrium condition in Hardy-Weinberg analysis. The association result showed that 2 SNPs (g.-7799T>C and g.-7941C>T) were significantly associated with intramuscular fat percentage (P≤0.05) in Bali cattle. Although the 2 SNPs were nominally significant at nominal P≤0.05 threshold, they were not significant after Bonferroni correction for multiple testing. It could be concluded that MSTN promoter gene was polymorphic in Bali cattle and there were 2 SNPs associated with carcass quality.
其他摘要：Gen myostatin (MSTN) berperan dalam homeostasis otot rangka seperti induksi athrophy otot, myosblast poliferasi, peningkatan ubiquitin-proteasomal, penurunan pathway IGF dan glikolisis. Ekspresi gen myostatin (MSTN) dikontrol oleh CpG island yang berlokasi di promoter. Tujuan dari penelitian ini adalah mengidentifikasi polimorfisme dari promoter gen MSTN dan mengasosiasikan polimorfisme dari SNP dengan sifat pertumbuhan dan perdagingan pada sapi Bali. Sebanyak 48 sapi Bali yang berasal dari BPTU-HMT pulau Bali diidentifikasi polimorfisme dari gen MSTN bagian promoter menggunakan metode sekuensing. Sifat pertumbuhan dan perdagingan diukur pada umur 12 bulan. Sifat perdagingan diukur menggunakan ultrasonografi dengan linier transduser dan pembacaan pada frekuensi 6,5Hz dan kedalaman 130 mm. Analisis polimorfisme dilakukan menggunakan software Popgen 1.32. Asosiasi gen MSTN dengan sifat pertumbuhan dan perdagingan dianalisis dengan menggunakan prosedur General Linear Model (GLM). Hasil penelitian ini menunjukkan sebanyak 20 SNP yang polimorfik ditemukan di daerah ini (7 SNP berada pada posisi CpG island). Namun, hanya ada 3 SNP, yaitu g.-8078C>T, g.-7996G>C and g.-7930A>G yang ditemukan dalam keadaan seimbang berdasarkan analisis Hardy-Weinberg. Hasil asosiasi ditemukan bahwa SNP g.-7799T>C dan g.-7941C>T berasosiasi nyata dengan sifat persentase lemak intramuskuler (P≤0,05). Meskipun 2 SNP tersebut signifikan pada P≤0,.05, namun tidak signifikan setelah dikoreksi Bonferroni untuk uji berganda. Dapat disimpulkan bahwa gen promotor MSTN polimorfik pada sapi bali dan terdapat 2 SNP yang berasosiasi dengan sifat kualitas karkas.
