Unstable DNA repair genes shaped by their own sequence modifying phenotypes.

摘要: The question of whether natural selection favors genetic stability or variability is a fundamental problem in evolutionary biology. Bioinformatic analyses demonstrate that by avoiding unstable nucleotide sequences protein encoding DNA. Yet, such are maintained several DNA repair genes, thereby promoting breakdown and destabilizing the genome. Several studies have therefore argued at expense stability. Here we propose new mechanism, with supporting bioinformatic evidence, resolves this paradox. Combining concepts gene-dependent mutation biases meiotic recombination, argue mismatch (MMR) genes their own phenotype. In particular, predict human MMR maintains an overrepresentation mononucleotide repeats (monorepeats) within around genes. support hypothesis, report 31% excess monorepeats 250 kb regions surrounding seven compared to all other RefSeq (1.75 vs. 1.34%, P = 0.0047), particularly high content PMS2 (2.41%, 0.0047) MSH6 (2.07%, 0.043). Based on mathematical model monorepeat frequency, proposed mechanism may suffice explain observed Our findings thus indicate through evolution mechanism. paradox genetically be explained equilibrium which phenotype acts back its genotype.