Thursday, September 01, 2005

Comparative genomics! What has it yielded till date?

Comparative genomics! What has it yielded till date? Comment keeping in view the recent sequence available from Chimp


Rajiv Narula said...

Scientists have already sequenced genomes of several prokaryotes & eukaryotes but the real revolution in genomics will take years to unfold.There are still many prokaryotes that might not only be uncultivable but also unclonable even wih the most non-specific set of PCR primers that have been tried.
even then comparitive genomics does work to give us information on gene functions and evolution as genome comparisons reveal important information on gene functions and evolution, as genome comparisons reveal important information on functions and evolutionary relationships of great majority of genes in any genome. As Darwin rightly puts it in the Origin of Species,written way back in 1859--The affinities of all beings of the same class have sometimes been represented by a great tree.I believe this Simile largely speaks the truth.

prash said...

It was really nice to see and learn lots much of things from the chimp genome. And probably, we could explore more of the evolutionary patterns as the sequence coverages are studied and enhanced.

No doubt, Comparative genomics has played a worth of it. But I think looking in to the other genomes(considering the various prokaryotic genomes sequenced with different strains)
our growing concern would be what comparative genomics has yielded so far?

The genomes studied so far have in idea that one strain, when sequenced could show-up the genes that might not turn up with other strain of the same species. So there could be some specific number of genes that could remain transient or associated with a given species. For example, it was described that each Group B Strep (GBS) strain contained an average of 1806 genes present in every strain plus 439 genes absent in one or additional strains. Furthermore, mathematical modeling showed that unique genes will continue to emerge, even after thousands of genomes are sequenced (TIGR, Public release date: 22-Sep-2005). This interpretation of microbial genomes was described as describing a species by its "pan-genome": the sum of a core genome, containing genes present in all strains, and a dispensable genome, with genes absent from one or more strains and genes unique to each strain.

So this is where we need to think!