[Campbell Biology P.359] What is the defining characteristic of genomic imprinting? | Practice Question

What is the defining characteristic of genomic imprinting?

  • A: It only affects genes located on sex chromosomes.
  • B: The expression of an allele depends on whether it is inherited from the male or female parent.
  • C: It involves the physical loss of a gene from one parent's chromosome.
  • D: It causes heterozygotes to have a phenotype intermediate between the two homozygotes.

Explanation

The text defines genomic imprinting as a 'variation in phenotype depending on whether an allele is inherited from the male or female parent.' This is a non-Mendelian pattern because it violates the assumption that the parental origin of an allele does not affect its expression.