Genomic analysis of hair sheep from West/Central Africa reveals unique
genetic diversity and ancestral links to breed formation in the
Caribbean
Abstract
Cameroon Blackbelly sheep are a domestic breed of hair sheep from
West/Central Africa. They are popular with small holder farmers in
Cameroon as they are highly resilient to local environmental challenges
and are prolific aseasonal breeders. The aim of this study was to
characterise the genetics of the Cameroon Blackbelly sheep in relation
to global sheep populations and to investigate their relationship to
Caribbean hair sheep. We first examined the genetic diversity of the
Cameroon Blackbelly breed relative to global sheep populations using 50K
SNP data. We also used whole genome sequence (WGS) data to further
investigate relationships between the Cameroon Blackbelly breed and
breeds from Africa and Europe, as well as the Barbados Blackbelly breed
from the Caribbean, which is phenotypically similar to Cameroon
Blackbelly. Admixture results based on 50K and WGS data demonstrated
both West/Central African and European ancestries for the Barbados
Blackbelly sheep. Local ancestry inference identified several genomic
regions in Barbados Blackbelly that had high proportions of West/Central
African ancestry. One of these regions, on OAR3, includes various
keratin genes, suggesting that these genes may play a role in the shared
coat phenotypes of Barbados Blackbelly and Cameroon Blackbelly. The
findings of our study support the view that sheep were transported from
West/Central Africa to the Caribbean as part of the slave trade and
European colonization. The genomic resources we have generated also
highlight the unique genetic diversity represented by West/Central
African sheep, their contribution to global breed formation, and the
importance of conserving genetic diversity.