Genetic structure of phenotypic robustness in the collaborative cross mouse diallel panel

Area of Science:

• Developmental biology
• Evolutionary genetics

Background:

• Developmental stability and canalization are crucial for minimizing phenotypic variation against environmental and genetic challenges.
• Understanding the genetic basis of phenotypic robustness remains a key challenge in developmental biology.

Purpose of the Study:

• To investigate the genetic architecture of phenotypic robustness, specifically developmental stability and canalization.
• To analyze fluctuating asymmetry and among-individual variation in cranial shape within the Collaborative Cross mouse population.

Main Methods:

• Utilized geometric morphometrics and Bayesian diallel analysis on reciprocal crosses within the Collaborative Cross mouse population.
• Assessed fluctuating asymmetry (FA) and among-individual variation in cranial shape.
• Analyzed additive, sex-specific, and strain-specific genetic effects.

Main Results:

• Significant genetic variation was identified for both developmental stability and canalization.
• Inbreeding showed a positive effect on both components of variation.
• The CAST/EiJ strain had a notable additive effect on FA and among-individual variance.

Conclusions:

• Phenotypic robustness, encompassing developmental stability and canalization, exhibits significant genetic variation.
• Robustness is not directly linked to phenotypic extremeness, challenging simple models of stabilizing selection.