JLT
Posts: 740
Joined: Jan. 2008
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Sternberg, as quoted by SlimeySal:
| Quote | Now, the problem with such a statement is this: While there are ~25,000 protein-coding genes in our DNA, the number of RNA-coding genes is predicted to be much higher, >450,000.[1] [...]
So the true number of genes in our DNA is probably “450,000 + 25,000 = 475,000?. |
From the abstract of the cited paper (the article is freely available here, but of course not linked at the Disco'tute):
| Quote | | Up to 450 000 non-coding RNAs (ncRNAs) have been predicted to be transcribed from the human genome. However, it still has to be elucidated which of these transcripts represent functional ncRNAs. Since all functional ncRNAs in Eukarya form ribonucleo-protein particles (RNPs), we generated specialized cDNA libraries from size-fractionated RNPs and validated the presence of selected ncRNAs within RNPs by glycerol gradient centrifugation. As a proof of concept, we applied the RNP method to human Hela cells or total mouse brain, and subjected cDNA libraries, generated from the two model systems, to deep-sequencing. Bioinformatical analysis of cDNA sequences revealed several hundred ncRNP candidates. Thereby, ncRNAs candidates were mainly located in intergenic as well as intronic regions of the genome, with a significant overrepresentation of intron-derived ncRNA sequences. Additionally, a number of ncRNAs mapped to repetitive sequences. Thus, our RNP approach provides an efficient way to identify new functional small ncRNA candidates, involved in RNP formation. |
The authors didn't look for ncRNAs in protein clusters bigger than 30S and they looked only at one cell type (not all ncRNAs are expressed in all cell types or at all times), so they probably missed a lot. OTOH, they haven't shown that all the identified novel ncRNAs are indeed functional, i.e. it isn't clear how sensitive their method is. Actually, they haven't shown that any of their novel ncRNAs are functional, they only identified candidates.
So, several hundred ncRNA candidates equal "probably 450 000 genes" in Sternberg's world. Fitting, they don't seem to realize the difference between 6000 and 4.5x10^9 years, either.
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"Random mutations, if they are truly random, will affect, and potentially damage, any aspect of the organism, [...]
Thus, a realistic [computer] simulation [of evolution] would allow the program, OS, and hardware to be affected in a random fashion." GilDodgen, Frilly shirt owner
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