One prediction of the neutral theory is that - One...

One prediction of the neutral theory is that silent (synonymous) sites in protein
coding regions will evolve faster than replacement (nonsynonymous) sites (due to
different functional constraints). This provides a null hypothesis about DNA
evolution. Most sequences fit this neutral model; however, the histocompatibility loci
appear to deviate from a neutral model in that there are more nonsynonymous
substitutions than synonymous substitutions. This holds only for the antigen binding
region; the rest of the molecule is consistent with neutral expectations. (see figure
7.10, pg. 185).
Another prediction of the neutral theory is that amount of sequence divergence will
be correlated with the level of heterozygosity ; heterozygosity is measured as 2pq
for a two allele situation or (2pq+2pr+2qr) for a three allele situation, or 1- x
i
2
for i
alleles; see figure 5.2 pg. 96 for a two allele view). Loci with high heterozygosity
should evolve at a faster rate under the assumption that these loci have a higher rate of
neutral mutation (thus more variation within species and more substitution between