For easy understanding, it can be said that transposons simply cut and paste certain segments of DNA sequence during the process of transposition. Once inserted into the host genome, transposons use nucleic acids to perform their task. However, transposons use different types of nucleic acids than retrotransposons. They use a substance called ‘transposase’ as a biological catalyst for speeding up their reaction and possess the ability to produce their own enzymes as well. Transposons can perform transposition independently and can cause mutations within the host genome. These elements can alter the code of the genes is they are inserted into the DNA and this can change the entire functioning of the genetic sequence.
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These elements produce intermediate RNA molecules during the transposition and if this RNA is synthesised, it can transform into DNA inside the genome. Retrotransposons also use nucleic acids for this purpose and they further require the enzyme called ‘reverse transcriptase’ for creating the RNA molecules. Retrotransposons act both independently and in non-autonomously ways, just like transposons. 42 per cent of human genome consists of retrotransposons, while transposons are just 2 to 3 per cent.
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