Interactions between @entity1880 and T-locus alleles during XXXX embryogenesis.

@entity1619 @entity19 @entity1880 @entity853 @entity2659 @entity600 @entity56515
Female @entity2659 @entity19 were mated with @entity2659 X T/ + F1 males that were heterozygous for the @entity1619 lethal gene or were +/+. Fetuses from @entity2659 X +/+ matings were normal when observed on gestation Day 17 (plug day = Day 0). Those from the @entity2659 X T/+ cross exhibited the expected 1:1 ratio of short:normal tail lengths, but 10% of these fetuses were tailless, apparently due to factors in the @entity2659 genotype that increased the expressivity of the T-gene with regard to reduction of tail length. Additional @entity2659 females were mated with @entity2659 X tw18/+ F1 males. Fetuses from the @entity2659 X tw18/+ matings were normal. @entity2659 females carrying @entity2659 X +/+, @entity2659 X T/+, or @entity2659 X tw18/+ litters were injected ip on gestation Day 9 with 30 mg/kg @entity1880 or were untreated. @entity1880 was teratogenic for litters from all three crosses. Polydactyly, @entity56515 , and a variety of @entity853 were observed. Gross @entity600 were increased in treated @entity2659 X T/ + or tw18/+ litters in comparison with @entity2659 X +/+ litters, as were nonvertebral skeletal defects in @entity2659 X tw18/+ litters. Prenatal mortality was also greater in treated mutant-containing litters than in +/+ litters, and fetal weights were similarly decreased in treated @entity2659 X tw18/+ litters. The incidence of taillessness was also higher in treated (26%) than in control (10%) @entity2659 X T/+ litters. Thus both the T and tw18 alleles appear to have enhanced the teratogenicity of @entity1880 , and the inhibitor may have increased the expressivity of T.
