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Updated: Jun 6, 2026
10:41
Rat Mammary Epithelial Cell Transplantation into the Interscapular White Fat Pad
Published on: March 4, 2020
Mapping the epistatic network underlying murine reproductive fatpad variation
Joseph P Jarvis1, James M Cheverud
1Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. jarvisj@mail.med.upenn.edu
Genetics
|December 1, 2010
Summary
Advanced intercross line mapping reveals extensive epistasis influencing mouse fatpad weight. This study identifies numerous novel epistatic loci and confirms their significant role in complex trait variation.
Area of Science:
- Genetics
- Quantitative Genetics
- Genomic Analysis
Background:
- Genome-wide mapping is common, but epistatic interactions contributing to complex traits remain poorly understood.
- Identifying epistatic quantitative trait loci (epiQTL) is challenging, especially in mammals, due to limited genetic resolution.
Purpose of the Study:
- To investigate the genetic architecture of reproductive fatpad weight in mice.
- To identify single-locus QTL (slQTL) and epistatic loci contributing to obesity in an advanced intercross line.
Main Methods:
- Utilized the F(10) generation of the LG,SM advanced intercross (AI) line for mapping.
- Applied single-locus models, composite interval mapping (CIM), and genome-wide scans for pairwise epistasis.
- Analyzed 12 chromosomes known to harbor slQTL for obesity.
Main Results:
- Detected 199 peaks across all 19 autosomes contributing to trait variation.
- Identified eight original F(2) loci (Adip1-8), novel slQTL on chromosomes 7 and 9, and several new epistatic loci.
- Confirmed extensive epistasis involving both slQTL confidence intervals and regions without significant additive or dominance effects.
Conclusions:
- Provides new insights into mapping complex genetic architectures.
- Highlights the significant role of epistasis in the variation of complex traits like fatpad weight.
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