Question

if twins are said to have 100% same DNA , then how do they have different fingerprints and cornea pattern?

Answer 1

Though identical twins share the same genome they develop separately in the mothers womb. Characteristics like fingerprints are not exclusively genetical. They are determined also by the environment that the baby faces in the womb. Fingerprints are actually pressure points faced by baby in the womb. So the environment causes changes in features in identical twins as well.