[Campbell Biology P.359] In the case of the mouse Igf2 gene, a heterozygote mouse inherits a... | Practice Question

In the case of the mouse Igf2 gene, a heterozygote mouse inherits a normal allele from its mother and a mutant dwarf allele from its father. What will be the phenotype of this mouse?

  • A: Normal-sized
  • B: Dwarf
  • C: Intermediate-sized
  • D: The phenotype cannot be determined.

Explanation

According to Figure 15.17, only the paternal allele of the Igf2 gene is expressed, while the maternal allele is silenced. In this case, the mouse inherited the mutant dwarf allele from its father. Therefore, only the mutant allele will be expressed, resulting in a dwarf mouse.