| A growing body of evidence suggests that divergence in the number of gene copies via gene duplication and deletion events plays a key role in adaptive evolution. Much of this evidence comes from comparisons of sequenced genomes from related species. For example, it has been noted that although the human and chimpanzee genomes are ∼99% identical at orthologous sequences, humans and chimpanzees differ in gene copy number by more than 6%. These results raise the question of the extent to which gene gain and loss events affect phenotypic diversity and are subject to natural selection. I aim to address this question by examining genomic copy number variants (CNVs), which are large duplication and deletion events segregating within populations. I will discuss the extent of copy number polymorphism in humans and model organisms, and show how the mutational patterns and population dynamics of CNVs can reveal the selective forces acting on these polymorphisms. |
