Exploring whole-genome duplicate gene retention with complex genetic interaction analysis

Whole-genome duplication has played a central role in genome evolution of
many organisms, including the human genome. Most duplicated genes are
eliminated and factors that influence the retention of persisting
duplicates remain poorly understood. Here, we describe a systematic
complex genetic interaction analysis with yeast paralogs derived from the
whole-genome duplication event. Mapping digenic interactions for a
deletion mutant of each paralog and trigenic interactions for the double
mutant provides insight into their roles and a quantitative measure of
their functional redundancy. Trigenic interaction analysis distinguishes
two classes of paralogs, a more functionally divergent subset and another
that retained more functional overlap. Gene feature analysis and modeling
suggest that evolutionary trajectories of duplicated genes are dictated by
combined functional and structural entanglement factors.