Layers of Cryptic Genetic Variation Underlie a Yeast Complex Trait

Area of Science:

• Genetics and Genomics
• Yeast Biology
• Molecular Biology

Background:

• Cryptic genetic variation contributes to heritable traits but remains poorly understood.
• Understanding the regulation and extent of cryptic genetic variation is crucial for trait heritability.
• A specific colony phenotype in Saccharomyces cerevisiae, typically suppressed, serves as a model for investigation.

Purpose of the Study:

• To investigate the cryptic genetic variation underlying a specific Saccharomyces cerevisiae colony phenotype.
• To comprehensively dissect the genetic basis of this trait in a BY4716 x 322134S cross.
• To identify loci interacting with genetic perturbations that enable trait expression.

Main Methods:

• Genetic analysis of a BY4716 x 322134S Saccharomyces cerevisiae cross.
• Comprehensive dissection of trait genetic basis under three different genetic perturbations.
• Identification and comparison of loci interacting with each perturbation.

Main Results:

• Twenty-one loci contributing to the trait were identified, with most interacting with only a subset of perturbations.
• Genetic perturbations modulated additivity, epistasis, and genotype-environment interactions among loci.
• The gene FLO11 was identified as the single locus interacting with all three perturbations; other loci influenced FLO11 transcription.

Conclusions:

• Cryptic genetic variation comprises layers of regulatory inputs into the transcription of key genes like FLO11.
• Genetic perturbations reveal distinct pathways and subpathways influencing trait expression.
• This study elucidates how cryptic genetic variation contributes to complex traits through gene regulation.