Induction of new mutations in a mouset-haplotype using ethylnitrosourea mutagenesis

Abstract

SummaryN-ethyl-N-nitrosourea (ENU) was used to induce mutations within thetw5-haplotype of the mouse to make possible a further study of gene arrangement int-mutants and to provide potential landmarks for cloning and sequence studies in the region. Two independent mutants were isolated for each of three loci in thet-region, brachyury (T), quaking (qk), and tufted (tf). The newTktalleles produce tailless mice when atctmutation is present intrans. The newqkktalleles are recessive and homozygous lethal. They are viable, male fertile, and cause seizures and quaking when paired with theqkmutation which previously defined the locus. Thetfktmutations are recessive and phenotypically similar to the mutant alleles available in non-tchromosomes. The mutations were induced in thetw5-haplotype at an average per locus frequency of 1 in 1500. Their isolation demonstrates the power of this technique for obtaining the specific mouse mutants that are needed to genetically dissect a complex mammalian system.