IDENTIFIKASI POLIMORFISME GEN Diacylglycerol Acyltransferase1 DAN KETERKAITANNYA DENGAN KADAR LEMAK SUSU KAMBING SAANEN

LAURENSIA M YULIAN, Prof. Dr. drh. Widya Asmara, SU; Dr. Widodo, S.P., M.Sc.

2017 | Tesis | S2 Bioteknologi

Marka gen bermanfaat untuk membantu proses seleksi ternak terhadap fenotipe tertentu yang bersifat komersial. Kambing Saanen memiliki keunggulan dalam sifat produksi susu. Salah satu sifat produksi susu yang komersial yaitu kadar lemak susu. Gen diacylglycerol acyltransferase 1 (DGAT1) terlibat dalam proses akhir sintesis trigliserida dan memiliki keterkaitan dengan kadar lemak susu. Perubahan nukleotida tunggal atau insersi-delesi pada sekuen tertentu dari gen DGAT1 dapat dijadikan marka genetik untuk sifat kuantitatif kadar lemak susu. Penelitian ini bertujuan untuk mengkaji perbedaan variasi kadar lemak susu antar individu kambing Saanen, mengidentifikasi polimorfisme ekson 14-16 gen DGAT1 dan mengkaji keterkaitan polimorfisme dengan kadar lemak susu kambing Saanen. Sampel darah dan susu dikoleksi, kemudian dilakukan isolasi DNA darah, amplifikasi gen DGAT1, sequencing, deteksi polimorfisme dengan metode Polymerase Chain Reaction-Single Strand Conformation Polymorphism (PCR-SSCP), dan uji kualitas susu pada 3 bulan laktasi menggunakan Lactoscan. Rata-rata produksi susu harian sebesar 2.340±709 ml/hari, 1.880±632 ml/hari, 1.432±536 ml/hari dan rata-rata kadar lemak susu sebesar 3,07±0,52%, 2,53±0,55%, 3,00±0,55%, berturut-turut untuk bulan laktasi pertama, kedua dan ketiga. Ukuran amplikon ekson 14-16 gen DGAT1 sepanjang ±350 bp. Identifikasi polimorfisme dengan PCR-SSCP menghasilkan pola monomorfis. Variasi kadar lemak susu kambing Saanen bukan disebabkan oleh polimorfisme ekson 14-16 gen DGAT1.

Gene markers are often usefull for selection process of cattle on commercial certain phenotypes. Saanen goat has predominance in milk production traits. Milk fat content is one of the commercial traits of milk production. Diacylglycerol Acyltransferase 1 (DGAT1) gene was involved in the final process of triglyceride synthesis and associated with milk fat content. Single nucleotide subtitution or insertion-deletion in certain sequence of DGAT1 gene could be gene markers for milk fat content. The objective of this study were to identify differences variation in milk fat content among individual Saanen goats, identify exon 14-16 polymorphism of DGAT1 gene and examine its correlation between polymorphism and milk fat content on Saanen goats. The methodologies were collection blood and milk samples, isolation DNA from blood, amplification of DGAT1 genes, sequencing, detection of polymorphism of exon 14-16 DGAT1 gene with Polymerase Chain Reaction-Single Strand Conformation Polymorphism (PCR-SSCP), and examination milk quality on three lactation months using Lactoscan. The average of daily milk production was approximately 2.340±709 ml/day, 1.880±632 ml/day, 1.432±536 ml/day and average of milk fat content was approximately 3,07±0,52%, 2,53±0,55%, 3,00±0,55% for the first, second and third months of lactation, respectively. The amplicon size of exon 14-16 of DGAT1 gene was ± 350 bp and showed monomorphic pattern from PCR-SSCP. Variation of milk fat content on Saanen goats not caused by polymorphism of exon 14-16 DGAT1 gene.

Kata Kunci : Saanen goat, milk fat content, DGAT1, polymorphism, PCR-SSCP