Genes sweat it out, too

 
Published: Saturday 30 September 2000

Heard of lean, trim genomes? According to Ken Shirasu and his colleagues at the John Innes centre in Norwich, Norfolk, genomes could possibly shed their flab. Around two-thirds of the deoxyribonucleic acid (dna) in some organisms is made up of repetitive sequences created by 'jumping genes'.

These genes are scientifically known as retrotransposons which are parasitic bits of dna that can replicate themselves at random. Examples abound in nature of crops with such 'overweight' genomes. The researchers, however, found that the barley genome contained fragments of retrotransposons known as single long terminal repeats.

This is indicative of the fact that large sections of repetitive dna have been removed. In the Genome Research, Shirasu is quoted as saying that this is not a random process. He has concluded that barley has the ability to control the size of its genome, possibly in response to the environment.

Subscribe to Daily Newsletter :

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.