The Genetic Variability of Prolactin and Signal Transducers and Activators of Transcription 5A (STAT5A) Genes in Bali Cattle

Abstract

The aim of this study was to identify the genetic variability of PRL and STAT5A genes in Bali cattle from Bali, West Nusa Tenggara (NTB), and South Sulawesi (SS) using PCR-RFLP method. A total of 262 Bali cattle were identified using RsaI (PRL) and AvaI (STAT5A) restriction enzymes. PRL gene exon 3, PRL gene exon 4, and STAT5A gene exon 7 amplifications resulted fragments with the lengths of 156 bp, 294 bp, 215 bp, respectively. Genotyping of PRL gene both at exon 3 and 4 produced three genotypes in Bali population and two genotypes in NTB and SS population. For the PRL gene, frequencies of A allele (exon 3) and G allele (exon 4) were dominant to the B allele (exon 3) and A allele (exon 4) across all populations. The results showed that STAT5A|AvaI loci had monomorphic C allele. Heterozygosity values were found low at both exons 3 and 4 of PRL gene in all population. Sequence analysis results of PRL gene both for exons 3 and 4 showed that there was a mutation between adenine (A) and guanine (G) bases in the RsaI recognized site, whereas in STAT5A gene we can confirm the existence of AvaI restriction site (C|CCGAG).

Penelitian ini bertujuan untuk mengidentifikasi ada tidaknya polimorfisme gen PRL dan STAT5A pada sapi bali di tiga daerah pusat pembibitan sapi bali, yaitu: Bali, Nusa Tenggara Barat (NTB), dan Sulawesi Selatan (SS) dengan menggunakan metode PCR-RFLP. Sapi bali sebanyak 262 sampel dideteksi keragaman genetiknya menggunakan enzim restriksi RsaI (PRL) dan AvaI (STAT5A). Amplifikasi gen PRL ekson 3, gen PRL ekson 4, dan gen STAT5A ekson 7 menghasilkan fragmen dengan panjang masing-masing 156 bp, 294 bp, dan 215 bp. Penentuan genotipe gen PRL ekson 3 dan ekson 4 menghasilkan tiga genotipe pada populasi di Bali dan dua genotipe pada populasi di NTB dan SS. Frekuensi alel A (ekson 3) dan alel G (ekson 4) lebih tinggi dibandingkan dengan alel B (ekson 3) dan alel A (ekson 4) untuk gen PRL. Hasil analisis menunjukkan bahwa lokus STAT5A|AvaI memiliki alel monomorfik C. Nilai heterozigositas ditemukan rendah pada gen PRL ekson 3 dan ekson 4 untuk seluruh populasi. Hasil sekuens fragmen gen PRL baik pada ekson 3 maupun ekson 4 menunjukkan adanya mutasi antara basa adenin (A) dengan guanin (G), sedangkan hasil analisis sekuens pada gen STAT5A dapat mengonfirmasi adanya situs restriksi enzim AvaI (C|CCGAG)