The above statement can be substantiated through DNA finger printing by southern blot method and by PCR.
DNA from all the cells of an individual shows the same degree of polymorphism.
The polymorphs are heritable. An individual and inherits 50% of the chromosomes from maternal and 50% from the paternal parent. Small amount of DNA from blood or tissue is taken and amplified by PCR, which can be used in DNA finger printing so as to identify the paternity.
