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bioRxiv · 10.1101/019513

Genetic interactions contribute less than additive effects to quantitative trait variation in yeast

Joshua S Bloom·Iulia Kotenko·Meru J Sadhu·Sebastian Treusch·Frank W Albert·Leonid Kruglyak
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Abstract

Genetic mapping studies of quantitative traits typically focus on detecting loci that contribute additively to trait variation. Genetic interactions are often proposed as a contributing factor to trait variation, but the relative contribution of interactions to trait variation is a subject of debate. Here, we use a very large cross between two yeast strains to accurately estimate the fraction of phenotypic variance due to pairwise QTL-QTL interactions for 20 quantitative traits. We find that this fraction is 9% on average, substantially less than the contribution of additive QTL (43%). Statistically significant QTL-QTL pairs typically have small individual effect sizes, but collectively explain 40% of the pairwise interaction variance. We show that pairwise interaction variance is largely explained by pairs of loci at least one of which has a significant additive effect. These results refine our understanding of the genetic architecture of quantitative traits and help guide future mapping studies.

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Joshua S Bloom, Iulia Kotenko, Meru J Sadhu, Sebastian Treusch, Frank W Albert, Leonid Kruglyak. 2015-05-19. Genetic interactions contribute less than additive effects to quantitative trait variation in yeast. https://doi.org/10.1101/019513

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