|
Register | Sign In |
|
QuickSearch
Thread ▼ Details |
|
Thread Info
|
|
|
Author | Topic: OMG!! Humans are more closely related to chimps than to other humans!!! | |||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
A very interesting paper is now online at Nature. It is entitled 'Global variation in copy number in the human genome' (Redon et al., 2006). The full article is freely available online.
We have recently had a number of threads discussing human/chimp genetics and the significance of indels on measurements of divergence and their significance to evolution. This paper studied copy number variations which include indels as well as duplications and more complex genetic events. This nature paper is a product of the haplotype mapping (HAPMAP) project which is being worked on by a number of HGP contributors such as the Sanger centre. The abstract is as follows...
Copy number variation (CNV) of DNA sequences is functionally significant but has yet to be fully ascertained. We have constructed a first-generation CNV map of the human genome through the study of 270 individuals from four populations with ancestry in Europe, Africa or Asia (the HapMap collection). DNA from these individuals was screened for CNV using two complementary technologies: single-nucleotide polymorphism (SNP) genotyping arrays, and clone-based comparative genomic hybridization. A total of 1,447 copy number variable regions (CNVRs), which can encompass overlapping or adjacent gains or losses, covering 360 megabases (12% of the genome) were identified in these populations. These CNVRs contained hundreds of genes, disease loci, functional elements and segmental duplications. Notably, the CNVRs encompassed more nucleotide content per genome than SNPs, underscoring the importance of CNV in genetic diversity and evolution. The data obtained delineate linkage disequilibrium patterns for many CNVs, and reveal marked variation in copy number among populations. We also demonstrate the utility of this resource for genetic disease studies. They identified 1,447 regions (CNVRs) in the genome where there were variations in copy number amongst the sampled genomes of sequences greater than 1Kb in size. These regions covered 12% of the genome altogether. They go on to show that copy number variations can be used to identify populations with putative common ancestry from european, asian and african populations. It would be interesting to see how these CNVRs compare to the regions of indels associated with the increased estimates in human chimp divergence. If both human and chimps can have as much as 12% variation based on CNVR's with populations then how much distinct difference do such factors present between the 2 species. This is really phenomenal work and as more organisms are studied at the same level of detail it opens up the possibility of identifying a vast area of functionally relevant variation both within and between mammalian species and throughout the animal kingdom. This also has major implications for the study of genetic differences affecting responses to medical treatments and to disease in general. There are at least 2 other CNV papers out related to this one, one in nature genetics (Khaja et al, 2006) and one in Genome Research which explains the technical methodology behind the comparisons in more detail(Fiegler et al., 2006) TTFN, WK Edited by Wounded King, : No reason given. Edited by Wounded King, : No reason given.
|
|||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
Perhaps this needs a sexier title like 'OMG!! Humans are more closely related to chimps than to other humans!!!'.
TTFN, WK
|
|||||||||||||||||||
AdminPhat Inactive Member |
Which Forum do you want this in, WK?
|
|||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
I'd have thought Biological Evolution was the most appropriate.
TTFN, WK
|
|||||||||||||||||||
AdminNem Inactive Member |
Thread moved here from the Proposed New Topics forum.
|
|||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
*bump* to see if a crass headline title can attract anyone's attention.
TTFN, WK
|
|||||||||||||||||||
mick Member (Idle past 4987 days) Posts: 913 Joined: |
Hi,
I don't have access to the literature right now, so could you explain what copy number variation is? I am thinking microsats and duplicated genes, but perhaps i am on the wrong track. [AbE] I know that microsatellites are the result of variation in copy number of nucleotide pairs, triplets, quadruplets, or whatever, and that the human population varies moderately in copy number. At a different order of magnitude, I know that duplicated genes might result in numerous copies of a protein-coding sequence, and that in this respect the human population is pretty constant in copy number. So I can only assume that the authors of the paper are talking about some intermediate level, perhaps variation in copy number of intronic elements or something like that? Mick Edited by mick, : No reason given.
|
|||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
I don't have access to the literature right now The paper is available without a subscription at the moment so you should be able to download it or read it online.
So I can only assume that the authors of the paper are talking about some intermediate level, perhaps variation in copy number of intronic elements or something like that? No and yes. Copy nuber variation can encompass both expansion of repeat as in microsatellites and gene duplications. As I briefly mentioned in the OP it is simply any sequence of 1Kb or greater and which varies in representation from a base genome. They go on to characterise further...
A CNV can be simple in structure, such as tandem duplication, or may involve complex gains or losses of homologous sequences at multiple sites in the genome Over half of the identified CNVs overlap genes identified in the refseq database and more than 99% overlap highly convserved non-coding regions (but not ultra-conserved elements). TTFN, WK
|
|||||||||||||||||||
Minnemooseus Member Posts: 3941 From: Duluth, Minnesota, U.S. (West end of Lake Superior) Joined: Member Rating: 10.0 |
Found this while bumbling around the older topics bin. I have recollections of having asked about this sort of topic before, but it doesn't seem to be in this topic.
Could we get the "Biology for Absolute Dummys" version? What human/human gap is larger than what human/chimp gap? Moose
|
|||||||||||||||||||
Doddy Member (Idle past 5910 days) Posts: 563 From: Brisbane, Australia Joined: |
What human/human gap is larger than what human/chimp gap? I just skimmed through the full text of the cited paper, and I can't see any answer to that. My thinking is that Wounded King is deliberately misleading us... I did see a study while I was searching around, by Perry, GH et al titled Hotspots for copy number variation in chimpanzees and humans (PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 103 (21): 8006-8011 MAY 23 2006). It seemed to be more on comparing the human/human and the chimp/chimp gap though:
quote: Maybe WK can explain where he got the idea for the title from? Contributors needed in the following fields: Physical Anthropology, Invertebrate Biology (esp. Lepidopterology), Biochemistry, Population Genetics, Scientific Illustration, Scientific History, Philosophy of Science, Logic and others. Researchers also wanted to source creationist literature references. Register here!
|
|||||||||||||||||||
Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
I chnaged the title from its original sober incarnation, which I can no longer recall, as a cheap way of attracting peole to the thread, a move which still singularly failed to excite much interest.
The basis of the title was the conflation by anti-evolutionist of virtually any measure of genetic distance as equivalent to any other and virtually interchangeable. When you look at the arguments of people like Eggasai who complain that because sequence similarity measured by a crude biochemical measure is not the same as when measured by a direct comparison of the genetic sequence, or that one based on SNPs is different from one based on indels, that there is some sort of cover up being perpetrated. Therefore published data suggesting a potential for divergence in ~12% of the genome between humans seems a prime target for the same sort of misconstruction. TTFN, WK
|
|
|
Do Nothing Button
Copyright 2001-2023 by EvC Forum, All Rights Reserved
Version 4.2
Innovative software from Qwixotic © 2024