DNA Hybridisation

• DNA hybridisation occurs when a section of DNA or RNA is combined with a single-stranded section of DNA which has complementary bases.
• Before hybridisation can occur, the two strands of the DNA molecule must be separated. This is achieved by heating the DNA until its double strand separates into two complementary single strands (denaturation).
• When the two separate DNA strands are cooled, the complementary bases on each strand recombine (anneal) with each other to reform the original double strand.
• If enough time is available, all strands in a mixture of DNA will pair up with their complementary strand when cooled. However, if other complementary sections also exist in the mixture, they are just as likely to anneal with another separate DNA strand than their other original strand.