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The landscape of genetic complexity across 5,700 gene expression traits in yeast.

ABSTRACT: Many studies have identified quantitative trait loci (QTLs) that contribute to continuous variation in heritable traits of interest. However, general principles regarding the distribution of QTL numbers, effect sizes, and combined effects of multiple QTLs remain to be elucidated. Here, we characterize complex genetics underlying inheritance of thousands of transcript levels in a cross between two strains of Saccharomyces cerevisiae. Most detected QTLs have weak effects, with a median variance explained of 27% for highly heritable transcripts. Despite the high statistical power of the study, no QTLs were detected for 40% of highly heritable transcripts, indicating extensive genetic complexity. Modeling of QTL detection showed that only 3% of highly heritable transcripts are consistent with single-locus inheritance, 17-18% are consistent with control by one or two loci, and half require more than five loci under additive models. Strikingly, analysis of parent and progeny trait distributions showed that a majority of transcripts exhibit transgressive segregation. Sixteen percent of highly heritable transcripts exhibit evidence of interacting loci. Our results will aid design of future QTL mapping studies and may shed light on the evolution of quantitative traits.

SUBMITTER: Brem RB

PROVIDER: S-EPMC547855 | biostudies-literature | 2005 Feb

REPOSITORIES: biostudies-literature

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The landscape of genetic complexity across 5,700 gene expression traits in yeast.

Brem Rachel B RB Kruglyak Leonid L

Proceedings of the National Academy of Sciences of the United States of America 20050119 5

Many studies have identified quantitative trait loci (QTLs) that contribute to continuous variation in heritable traits of interest. However, general principles regarding the distribution of QTL numbers, effect sizes, and combined effects of multiple QTLs remain to be elucidated. Here, we characterize complex genetics underlying inheritance of thousands of transcript levels in a cross between two strains of Saccharomyces cerevisiae. Most detected QTLs have weak effects, with a median variance ex ...[more]

PMID: 15659551

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Dataset Information

The landscape of genetic complexity across 5,700 gene expression traits in yeast.

Publications

The landscape of genetic complexity across 5,700 gene expression traits in yeast.

Similar Datasets

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