Insight into the Genetic History of South African Sanga Cattle from Dense SNP Data on Worldwide Breeds

Sanga cattle are believed to be a cross between Bos indicus and Bos taurus cattle, which is assumed to have taken place between the cattle migrating south from Egypt and Sudan, and the cattle that migrated from Arabia and India. This is based on the hypothesis that mixing of the Egyptian Longhorn with Lateral Horned Zebu cattle resulted in the Sanga.  On the other hand, some suggests that the Sanga originated from a cross of the Egyptian Longhorn with Brachyceros. It is therefore unclear whether the Sanga originated from a Bos indicus cross with Bos taurus or is the result of natural selection from cattle originating from only one of the first two postulated domestication sites. The objective of this study was to assess the population structure of South African Sanga (Afrikaner, Nguni and Bonsmara) cattle relative to 148 cattle breeds of the world. Patterns of ancestry and admixture was assessed using model-based clustering (ADMIXTURE). Results of this study indicated that South African Sanga cattle had a little influence (≤0.1) from Bos indicus breeds (Brahman, Nelore, Gir and Boran). Nguni cattle shared 30 % of its genome with the Zebu cattle, while the Afrikaner cattle was shown to have little influence (0.7 %) from the Zebu cattle.  This study supported the hybrid nature of the Bonsmara cattle with its genome derived mainly from Nguni (13.4) %, Afrikaner (41.0%), Beef-Shorthorn (26.7 %) and Hereford (0.5 %). Results presented here will serve as the basis towards better understanding of the origin of the South African Sanga cattle.