Who knows a reliable method for calculating divergence time between members
of a multigene family, with the members having different evolutionary rates?
Between orthologous sequences synonymous substitution rates are fairly
constant (3*10-9 per site per year), while nonsynonymous substitution rates
range from 0.021-0.76*10-9. Between paralogous sequences the number of
synonymous substitutions can not be accurately estimated, so use of
non-synonymous differences seems necessary.