Genetic Variation of Kappa-Casein in Sudanese Goats

The aim of this study is to characterize four Sudanese goat breeds, identify genetic variation of the diacylglycerol acyltransferase 1 (DGAT1) gene and the milk protein genes alpha-S1 casein (CSN1S1), alpha-S2 casein (CSN1S2), beta casein (CSN2), kappa casein (CSN3), alpha-lactalbumin (LALBA), and milk beta-lactoglobulin (MBLG), perform an association study between sequence variation and milk yield and composition, and to investigate the genetic diversity among Saanen and Sudanese goat breeds using the goat SNP50 Beadchip. The proposed breeds include four Sudanese indigenous breeds (Nubian, Nilotic, Desert and Dwarf goats) and the exotic Saanen goat as a control group (100 from each native breed and 50 from Saanen dairy goats). Milk yield and composition, reproductive performance, morphological characteristics and longevity are recorded as phenotypes. Candidate genes will be comparatively sequenced and sequence variation will be used for association tests. For assessing the genetic diversity among goat breeds, eight to ten animals per breed will be genotyped genome-wide, using the goat SNP50 BeadChip from Illumina. The long term goal of this study is the identification of selection markers to improve the productivity of native goats in developing countries, especially under the environmental conditions in Sudan.