Identifikasi Keragaman Gen Pituitary-Spesific Positive Transcription Factor 1 (Pit1|StuI) Exon 3 pada Sapi FH dengan Metode PCR-RFLP

Abstract

Pituitary-Specific Positive Transcription Factor 1 (Pit1, POUIF1 or GHF1) gene is a member of the tissue-specific POU-containing transcription factor family. The expression of Pit1 in mammalian pituitary gland is to control the transcription of the genes encoding growth hormone, prolactin (PRL) and the subunits of thyroid-stimulating hormone. This study was aimed to identify polymorphism of the pituitary specific positive transcription factor 1 (Pit1) exon 3 gene in Holstein Friesian (HF) cattle. Total number of samples were 286 heads from BIB Lembang (14), BBIB Singosari (25), BPPT-SP Cikole (81), KPSBU Pasir Kemis (93), and KPSBU Cilumber (73) using PCR-RFLP method by StuI restriction enzyme. Genotyping the Pit1 exon 3 gene resulted in two alleles, namely A and C , with three genotypes, namely AA, AC, and CC. The average frequency of the C allele followed by HF cattle in five places was higher (0,916) than the A allele (0,084). CC genotype had the highest average frequency (0,874) than the AC genotype (0,084) and the AA genotype (0,042). Chi-Square analysis showed that HF from BBIB Singosari were in Hardy-Weinberg (HW) equilibrium (2 < 2(0,05)), contrast to HF from BPPT Cikole and KPSBU Pasir Kemis (2 > 2(0,05)) and HF in BIB Lembang and KPSBU Cilumber could not be calculated equilibrium HW. The average values of heterozigosity observation (Ho) for HF studied were under the values of heterozigosity expectation (He), therefore the genetic variation of the Pit1|StuI exon 3 gene was low in these cattles.