Fertility and incidence of anal atresia in TC/+ mice associated with genetic background
| Genetic background . | Percentage of successful matings* . | Total number of litters . | Average litter size (average number of litters per pair) . | +/+ Offspring (% with anal atresia) . | TC/+ Offspring (% with anal atresia) . | P-value for χ2 analyses of Mendelian inheritance . |
|---|---|---|---|---|---|---|
| C3.Cg-TC | 48.9 | 38 | 6.2 (2.2) | 165 (0) | 73 (33.0†) | ≤1 × 10−13 |
| B6.C3(Cg)-TC | 45.8 | 30 | 6.6 (2.7) | 117 (0) | 81 (19.8‡) | ≤0.001 |
| STOCK-TC/JDown | 69.2 | 141 | 8.1 (3.9) | 586 (0) | 557 (6.29§) | 0.26 |
| Genetic background . | Percentage of successful matings* . | Total number of litters . | Average litter size (average number of litters per pair) . | +/+ Offspring (% with anal atresia) . | TC/+ Offspring (% with anal atresia) . | P-value for χ2 analyses of Mendelian inheritance . |
|---|---|---|---|---|---|---|
| C3.Cg-TC | 48.9 | 38 | 6.2 (2.2) | 165 (0) | 73 (33.0†) | ≤1 × 10−13 |
| B6.C3(Cg)-TC | 45.8 | 30 | 6.6 (2.7) | 117 (0) | 81 (19.8‡) | ≤0.001 |
| STOCK-TC/JDown | 69.2 | 141 | 8.1 (3.9) | 586 (0) | 557 (6.29§) | 0.26 |
The total live-born offspring recovered from TC/+X+/+ matings was used to determine expected values for ϰ2 analyses on each genetic background. For C3H.Cg-TC,B6.C3(Cg)-TC and STOCK-TC/JDown,ϰ2=35.56, 6.55 and 0.74, respectively.
† 8.33%, ‡75.0% and §28.5% of these also displayed hindlimb defects and a grossly shortened body.
At least 24 breeding pairs of each background were paired continuously for 4 months. Failure to produce a litter within this window was classified as infertile.