What is the expected outcome when a person (twin A) experiences a large deletion of DNA in one of his noncoding regions and his monozygotic twin (twin B) doesnot?
A)DNA identification of each twin will be more specific.
B)Only their somatic cells will remain identical at all loci.
C)Only their germline cells will remain identical at all loci.
D)They will now be dizygotic twins instead of monozygotic twins.

Question

Quizplus · Accepted Answer

Mutations of any type that occur in noncoding regions are responsible for making one person's DNA different from and identifiable from another person's DNA. Even identical twins (monozygotic twins) do not have absolutely identical DNA by the time they are born, although they probably did when the embryo first split into two embryos. By the time identical twins are born, they usually have at least 100 base pairs different from each other in the noncoding regions. As they live their lives, each twin continues to accumulate more and different mutations so that as they age, these identical twins become less identical in their DNA.

What Is the Expected Outcome When a Person (Twin A)