Positive selection in the tetherin gene.

Codon-specific rates of synonymous (dS) and non-synonymous (dN) nucleotide substitutions were estimated by Random Effect Likelihood methods under the MG94xHKY85 model of evolution. The Bayesian posterior probability for positive selection is given for each codon position. A Bayes factor of greater than 20 at a given site was considered to be strong support for positive selection. *Codon positions according to the human tetherin sequence (NM004335). Codons in the trans-membrane region are indicated in bold. **Posterior probability for positive selection (dN>dS) at the site.