What are satellite DNA in a genome? Explain their role in DNA fingerprinting.
Satellite DNA in a genome: In DNA there are sequences of nucleotides which are repeated many times known as repetitive DNA. These repetitive DNA are separated from bulk genomic DNA on the basis of peak formation during density gradient centrifugation. The bulk DNA forms major peak and the other forms minor peak and are known as satellite DNA.
Role in DNA fingerprinting :
1. These sequences show high degree of polymorphism, since DNA from every tissue (such as blood, hair follicle, skin, bone, saliva, sperm etc.) of an individual show same degree of polymorphism. They become very useful identification tools in forensic application.
2. Polymorphism is also quite similar in parents and children so it also helps in testing the paternity in case disputes.