What is satellite DNA ? Name their two types. Mention the basis for their classification.

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Satellite DNA refers to the repetitive DNA sequences, which do not code for any proteins, but form a large portion of human genome; they show high degree of polymorphism.

Types of satellite DNA are:
(i) micro satellites
(ii) mini satellites

The criteria for their classification includes :

(i) Base composition— A : T rich or G : C rich

(ii) Length of segment

(iii) Number of repetitive units.