Free Republic
Browse · Search
News/Activism
Topics · Post Article

Skip to comments.

Scientists Analyze Chromosomes 2 and 4: Discover Largest "Gene Deserts"
National Human Genome Research Institute ^ | 06 April 2005 | Staff

Posted on 04/13/2005 6:20:23 PM PDT by PatrickHenry

A detailed analysis of chromosomes 2 and 4 has detected the largest "gene deserts" known in the human genome and uncovered more evidence that human chromosome 2 arose from the fusion of two ancestral ape chromosomes, researchers supported by the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health (NIH), reported today.

In a study published in the April 7 issue of the journal Nature, a multi-institution team, led by [load of names deleted, but available in the original article].

"This analysis is an impressive achievement that will deepen our understanding of the human genome and speed the discovery of genes related to human health and disease. In addition, these findings provide exciting new insights into the structure and evolution of mammalian genomes," said Francis S. Collins, M.D., Ph.D., director of NHGRI, which led the U.S. component of the Human Genome Project along with the DOE.

Chromosome 4 has long been of interest to the medical community because it holds the gene for Huntington's disease, polycystic kidney disease, a form of muscular dystrophy and a variety of other inherited disorders. Chromosome 2 is noteworthy for being the second largest human chromosome, trailing only chromosome 1 in size. It is also home to the gene with the longest known, protein-coding sequence - a 280,000 base pair gene that codes for a muscle protein, called titin, which is 33,000 amino acids long.

One of the central goals of the effort to analyze the human genome is the identification of all genes, which are generally defined as stretches of DNA that code for particular proteins. The new analysis confirmed the existence of 1,346 protein-coding genes on chromosome 2 and 796 protein-coding genes on chromosome 4.

As part of their examination of chromosome 4, the researchers found what are believed to be the largest "gene deserts" yet discovered in the human genome sequence. These regions of the genome are called gene deserts because they are devoid of any protein-coding genes. However, researchers suspect such regions are important to human biology because they have been conserved throughout the evolution of mammals and birds, and work is now underway to figure out their exact functions.

Humans have 23 pairs of chromosomes - one less pair than chimpanzees, gorillas, orangutans and other great apes. For more than two decades, researchers have thought human chromosome 2 was produced as the result of the fusion of two mid-sized ape chromosomes and a Seattle group located the fusion site in 2002.

In the latest analysis, researchers searched the chromosome's DNA sequence for the relics of the center (centromere) of the ape chromosome that was inactivated upon fusion with the other ape chromosome. They subsequently identified a 36,000 base pair stretch of DNA sequence that likely marks the precise location of the inactived centromere. That tract is characterized by a type of DNA duplication, known as alpha satellite repeats, that is a hallmark of centromeres. In addition, the tract is flanked by an unusual abundance of another type of DNA duplication, called a segmental duplication.

"These data raise the possibility of a new tool for studying genome evolution. We may be able to find other chromosomes that have disappeared over the course of time by searching other mammals' DNA for similar patterns of duplication," said Richard K. Wilson, Ph.D., director of the Washington University School of Medicine's Genome Sequencing Center and senior author of the study.

In another intriguing finding, the researchers identified a messenger RNA (mRNA) transcript from a gene on chromosome 2 that possibly may produce a protein unique to humans and chimps. Scientists have tentative evidence that the gene may be used to make a protein in the brain and the testes. The team also identified "hypervariable" regions in which genes contain variations that may lead to the production of altered proteins unique to humans. The functions of the altered proteins are not known, and researchers emphasized that their findings still require "cautious evaluation."

In October 2004, the International Human Genome Sequencing Consortium published its scientific description of the finished human genome sequence in Nature. Detailed annotations and analyses have already been published for chromosomes 5, 6, 7, 9, 10, 13, 14, 16, 19, 20, 21, 22, X and Y. Publications describing the remaining chromosomes are forthcoming.

The sequence of chromosomes 2 and 4, as well as the rest of the human genome sequence, can be accessed through the following public databases: GenBank (www.ncbi.nih.gov/Genbank) at NIH's National Center for Biotechnology Information (NCBI); the UCSC Genome Browser (www.genome.ucsc.edu) at the University of California at Santa Cruz; the Ensembl Genome Browser (www.ensembl.org) at the Wellcome Trust Sanger Institute and the EMBL-European Bioinformatics Institute; the DNA Data Bank of Japan (www.ddbj.nig.ac.jp); and EMBL-Bank (www.ebi.ac.uk/embl/index.html) at EMBL's Nucleotide Sequence Database. [Links in original article.]

NHGRI is one of the 27 institutes and centers at NIH, an agency of the Department of Health and Human Services. The NHGRI Division of Extramural Research supports grants for research and for training and career development at sites nationwide. Additional information about NHGRI can be found at www.genome.gov.


TOPICS: Culture/Society; Miscellaneous; Philosophy
KEYWORDS: chromosomes; crevolist; dna; evolution; genetics
Navigation: use the links below to view more comments.
first previous 1-20 ... 81-100101-120121-140 ... 381-398 next last
To: Ichneumon

Ah, so you going to believe some Commie because he says so?


101 posted on 04/13/2005 9:44:07 PM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 97 | View Replies]

To: El Gato

Does it say god created a sea creature that transformed into an ape that evolved into a human? i think not, I believe it says something like 'god created man.'


102 posted on 04/13/2005 9:45:41 PM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 100 | View Replies]

To: jennyp
But they sorta look like what that mouse/human chimera would look like if they took that experiment too far!

An interesting observation, if you think about it a little bit.

103 posted on 04/13/2005 9:47:34 PM PDT by El Gato (Activist Judges can twist the Constitution into anything they want ... or so they think.)
[ Post Reply | Private Reply | To 96 | View Replies]

To: Cowboy Bob
If we evolved from apes, what did apes evolve from? I've never had that question answered.

Transitional Vertebrate Fossils FAQ

104 posted on 04/13/2005 9:51:34 PM PDT by Ichneumon
[ Post Reply | Private Reply | To 29 | View Replies]

To: El Gato
Our ancestor probably looked more like this:

It was somewhere between a modern tarsier and a modern galago, and that's the nearest to it.

105 posted on 04/13/2005 10:03:00 PM PDT by AntiGuv (™)
[ Post Reply | Private Reply | To 91 | View Replies]

To: freedumb2003; Echo Talon
I am sure you see electricity as magic and that when lightning strikes it is "God is Angry."

Ben Franklin's Unholy Lightning Rod

106 posted on 04/13/2005 10:06:03 PM PDT by qam1 (There's been a huge party. All plates and the bottles are empty, all that's left is the bill to pay)
[ Post Reply | Private Reply | To 94 | View Replies]

To: qam1

can electricity be studied? proven? meet all 3 criteria? yes. evolution does not. You keep believing your a monkey and I will believe you are a creation of the lord in his image.


107 posted on 04/13/2005 10:10:04 PM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 106 | View Replies]

To: Dog Gone

"advancement" is not a term to be bandied about concerning genetics.

just because we dominate the world with our wits and hands does not mean that the molecular structure of our genes is any slicker than that of any other mammal.


108 posted on 04/13/2005 10:22:46 PM PDT by King Prout (blast and char it among fetid buzzard guts!)
[ Post Reply | Private Reply | To 3 | View Replies]

To: Echo Talon
Ah, so you going to believe some Commie because he says so?

No, I'm going to believe the vast mountains of evidence supporting evolution, which I've personally studied.

109 posted on 04/13/2005 10:33:49 PM PDT by Ichneumon
[ Post Reply | Private Reply | To 101 | View Replies]

To: Ichneumon
No, I'm going to believe the vast mountains of evidence supporting evolution, which I've personally studied.

1. The postulate can't be observed.

2. The postulate can't be repeated for experimental verification.

3. The postulate must withstand a falsifiability test, or an experiment must be conceived the failure of which would disprove the postulate.

as your theroy doesnt meet the criteria to even be a theroy you have great chutzpah to believe in it.

110 posted on 04/13/2005 10:42:42 PM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 109 | View Replies]

To: Echo Talon
[No, I'm going to believe the vast mountains of evidence supporting evolution, which I've personally studied.]

1. The postulate can't be observed.

Sure it can. I've observed evolution occurring.

2. The postulate can't be repeated for experimental verification.

Sure it can. Hint for the clueless: *Verifications* need to be repeatable, not specific *events*. We don't have to actually be able to repeatedly move continents around in order to be able to repeatedly verify plate tectonics.

Events like the specific movements of the continents over the past several hundred million years -- or the evolution of modern life forms -- leave countless traces of their passage, which can be *repeatedly* verified in different ways in order to verify that they did, indeed, occur, and by what processes.

3. The postulate must withstand a falsifiability test, or an experiment must be conceived the failure of which would disprove the postulate.

Of course -- like this: 29+ Evidences for Macroevolution: The Scientific Case for Common Descent. Be sure to read the sections on "Potential Falsifications", as well as the page on the scientific method, since you seem quite confused about how it actually works.

as your theroy doesnt meet the criteria to even be a theroy you have great chutzpah to believe in it.

As it *does* meet the criteria of a scientific theory, *and* has made huge numbers of specific predictions which have been found to be accurate, *and* passed vast numbers of falsification tests with flying colors, you have great chutzpah in making false accusations based on your lack of knowledge on this topic.

Are you sure you know what in the heck you're talking about? Because it sure doesn't look like it from here.

111 posted on 04/13/2005 11:54:07 PM PDT by Ichneumon
[ Post Reply | Private Reply | To 110 | View Replies]

To: Ichneumon

pretty strange that not one, chimp-human has ever been found...


112 posted on 04/14/2005 12:11:27 AM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 111 | View Replies]

To: Ichneumon

also strange that humans haven't reverted back... at least in a few births... How come they ALL evolved? hmmm you keep sticking with your nonsense and I will stick with the truth.


113 posted on 04/14/2005 12:18:17 AM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 111 | View Replies]

To: Ichneumon
1. The postulate can't be observed.

Sure it can. I've observed evolution occurring.

you have observed exactly what? microevolution or macroevolution? uh huh thats what I thought.

114 posted on 04/14/2005 12:22:52 AM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 111 | View Replies]

To: Echo Talon
also strange that humans haven't reverted back... at least in a few births... How come they ALL evolved?


There are over a hundred documented case of such tails in humans.

115 posted on 04/14/2005 12:30:31 AM PDT by dread78645 (Sarcasm tags are for wusses.)
[ Post Reply | Private Reply | To 113 | View Replies]

To: dread78645

hmmm apes dont have tails...


116 posted on 04/14/2005 12:34:24 AM PDT by Echo Talon (http://echotalon.blogspot.com)
[ Post Reply | Private Reply | To 115 | View Replies]

To: Echo Talon
pretty strange that not one, chimp-human has ever been found...

Not one -- dozens: Prominent Hominid Fossils, Hominid Species

And this chart is several years out of date -- many more have been found in the past few years.

117 posted on 04/14/2005 12:36:19 AM PDT by Ichneumon
[ Post Reply | Private Reply | To 112 | View Replies]

To: Echo Talon
[Sure it can. I've observed evolution occurring.]

you have observed exactly what? microevolution or macroevolution?

Yes.

uh huh thats what I thought.

Are the voices in your head answering your own questions for you? If so, they're answering them incorrectly.

118 posted on 04/14/2005 12:55:38 AM PDT by Ichneumon
[ Post Reply | Private Reply | To 114 | View Replies]

To: Echo Talon
also strange that humans haven't reverted back... at least in a few births... How come they ALL evolved? hmmm you keep sticking with your nonsense and I will stick with the truth.

I'd be happy if you even started making *sense*... Your reaching the truth is unfortunately too much to hope for.

119 posted on 04/14/2005 12:56:36 AM PDT by Ichneumon
[ Post Reply | Private Reply | To 113 | View Replies]

To: Echo Talon
apes dont have tails...

No, but our common ancestor did.



120 posted on 04/14/2005 12:59:48 AM PDT by dread78645 (Sarcasm tags are for wusses.)
[ Post Reply | Private Reply | To 116 | View Replies]


Navigation: use the links below to view more comments.
first previous 1-20 ... 81-100101-120121-140 ... 381-398 next last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
News/Activism
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson