| Type | MGI:General | Description | 4.6-4.7% of expected numbers of double null animals from a parental cross of double heterozygotes are observed at P14; survivors to P14 exhibit a normal lifespan and are fertile when double heterozygous mice are bred to double null animals, around 7.6% of expected survivors are observed at P14, suggesting a survival-enhancing modifier transmitted by viable double null mice on a 129/Sv background, no viable animals are found at P14, while on a predominantly C57BL/6 background, about 1.4% of expected numbers of double null animals are found when animals are backcrossed to outbred ICR mice, animals are observed at 6.4% of expected numbers |
