Bits of Mystery DNA, Far From ‘Junk,’ Play Crucial Role
05/09/12 13:09 Filed in: New York Times
Submitted by Steven Pelech on Wed 09/05/2012 at 14:59
Less than 3% of the human genome actually encodes proteins or RNA. Many promoter, repressor and other regulatory elements control their expressions as well as genome and chromosome structure, replication, repair, and degradation. Encode is clearly a major advancement in their mapping within the genome.
That being said, over 8% of the human genome features remnants of viral DNA that was integrated into the genomes of our ancestors over millions of years. But the main reason why I have a hard time accepting that about 80% of the human genome sequence is functional and important is the data from other species. For example, the fruit fly Drosophila melanogaster has 0.165 billion nucleotide base pairs (nbp) in its genome, whereas the flower Fritillaria assyriaca has 124.9 billion nbp. The human genome size lies between with about 3.2 billion nbp.
It is likely that there is a strong evolutionary pressure to retain excess baggage so as to simply make sure that the important parts are retained. DNA sequencing studies in diverse organisms have increasingly demonstrated extreme ranges in the sizes of their genomes, whilst still having a relatively similar number of genes. It seems highly unlikely that this is simply for massively increasing the amount of regulation of genes in certain organisms over others.
Link to the original blog post
Less than 3% of the human genome actually encodes proteins or RNA. Many promoter, repressor and other regulatory elements control their expressions as well as genome and chromosome structure, replication, repair, and degradation. Encode is clearly a major advancement in their mapping within the genome.
That being said, over 8% of the human genome features remnants of viral DNA that was integrated into the genomes of our ancestors over millions of years. But the main reason why I have a hard time accepting that about 80% of the human genome sequence is functional and important is the data from other species. For example, the fruit fly Drosophila melanogaster has 0.165 billion nucleotide base pairs (nbp) in its genome, whereas the flower Fritillaria assyriaca has 124.9 billion nbp. The human genome size lies between with about 3.2 billion nbp.
It is likely that there is a strong evolutionary pressure to retain excess baggage so as to simply make sure that the important parts are retained. DNA sequencing studies in diverse organisms have increasingly demonstrated extreme ranges in the sizes of their genomes, whilst still having a relatively similar number of genes. It seems highly unlikely that this is simply for massively increasing the amount of regulation of genes in certain organisms over others.
Link to the original blog post