An inherited mild middle-aged adiposity in wild mice

Area of Science:

• Genetics
• Obesity Research
• Animal Models

Background:

• A dominant gene for adiposity (Ad) was identified in a laboratory-reared, warfarin-resistant wild mouse population.
• Obesity onset occurs between 4-6 months, with affected mice exhibiting hyperinsulinemia.
• Sex-specific differences in gene penetrance were observed, with males showing higher penetrance than females.

Purpose of the Study:

• To identify and characterize the genetic basis of obesity in a specific wild mouse population.
• To determine the chromosomal location and linkage of the adiposity gene (Ad).
• To explore the ecological and physiological implications of the Ad gene in wild populations.

Main Methods:

• Segregation analysis of the dominant adiposity gene (Ad) in a laboratory-reared mouse population.
• Linkage backcrosses to determine gene mapping and recombination frequencies.
• Comparative analysis of Ad gene presence in other wild mouse populations.

Main Results:

• The dominant adiposity gene (Ad) was found to segregate in the studied mouse population.
• The Ad gene is located on chromosome 7, with approximately 25% recombination with warfarin-resistance (War) and frizzy (fr) genes.
• The Ad gene was also found in two other wild populations that carry the War gene.

Conclusions:

• A novel dominant gene (Ad) linked to obesity and hyperinsulinemia has been identified in wild mice.
• The genetic linkage of Ad with War suggests potential co-evolutionary or pleiotropic effects.
• The prevalence of the Ad gene in multiple wild populations highlights its significance as an ecological and physiological concern.