Certain genes have apparently unusual inheritance patterns. For instance, in the mouse autosomal gene H19, only the copy inherit
ed from the mouse's mother is expressed. Conversely, in the mouse autosomal gene Igf2, only the copy inherited from the mouse's father is expressed. The consequence of this is that imprinted genes are expressed as if they were present in only one copy, even though there are two copies of each of these genes in each cell. What process or processes are responsible for this phenomenon? (Select all that apply.)None of the answer options is correct.combinatorial gene regulationepigenetic inheritanceX-chromosome inactivationMendelian inheritance
This phenomenon is known as genomic imprinting. Epigenetic control and inheritance is the basis of genomic imprinting: DNA methylation and histone methylation lead to inactivation (silencing) of a certain genes. The epigenetic pattern is imprinted and maintained in parents.
As a consequence of genomic imprinting, specific genes from only one parent are expressed. This is different than Mendelian type of inheritance in which in diploid cell one gene is from father while another is from mother.
Let's call the colour alleles C for dominant purple, and c for recessive white.
We have crossed Cc with Cc. So if we put that in a Punnett square, we'd have a CC, two Cc and a cc. That would give us a 3:1 ratio of purple to white, so you'd expect 15 purple and 5 white flowers. :)
