Structural vs. functional mechanisms of duplicate gene loss following whole genome doubling

The process of whole genome doubling (WGD) gives rise to two copies of each chromosome in a genome, containing the same genes in the same order. Through an attrition mechanism known as fractionation, one of each pair of duplicate genes is lost over evolutionary time, resulting in an interleaving patterns of deletions from duplicated regions [1]. This differentiates the WGD/fractionation model from general approaches to gene duplication, pioneered by El-Mabrouk [2].