What genome-wide markers revealed about native lines

A 2012 PLOS ONE study by James Kijas and colleagues examined 49,034 genetic markers to investigate structure within Gulf Coast Native sheep. Animals clustered largely according to Florida Native or Louisiana Native membership. The work supplied genetic evidence for distinctions that breeders had previously described through geography and appearance.

The study estimated differentiation between those two sampled populations at FST = 6.2 percent, exceeding its average comparison among recognized breeds developed in the same European region. FST describes differences in allele frequencies between populations; it does not mean that their genomes are only 93.8 percent alike.

The authors interpreted separation and genetic drift as major contributors. They found suggestive differences around the horn/poll region, but these did not explain most of the overall divergence. Their findings supported treating the native lines as distinct conservation resources. The paper does not identify the precise historical mix of imported ancestors, and it is not a current census. Its central lesson is that geographically related sheep can retain important genetic structure that broad labels and similar appearance conceal.