It is a general assumption that identical twins share exactly the same DNA because they arise from the same fertilized egg. However, SNP studies show that they are only about 99% identical. Where might the 1% difference have come from?
A)Mutations arise in somatic cells.
B)Mutations arise in gametic cells.

Question

Quizplus · Accepted Answer

Mutations in somatic cells can occur after the zygote has split into two embryos, leading to slight genetic differences between identical twins. These mutations can accumulate over time, contributing to the 1% difference in their DNA.

It Is a General Assumption That Identical Twins Share Exactly