Posted on 07/19/2009 7:46:56 PM PDT by djf
Oh this is going to complicate matters.
No!
Now they're going to need MORE funding to investigate this further to see if someone else's research is correct.
A scientist's pipe dream.
Good question. First cell splits into 2,4,8, 16, etc., and at some point some of the cells have to start forming different parts of the body.
Why this group of cells and not another? Spatial relationship? Biological clocks in some cells running fast or slow?
DNA just a mite more complicated than anyone has guessed, perhaps.
A scientist's pipe dream.
In all reality Global Warming is the scientists wet dream.
I don’t think this is a matter of genes switching on and off - these appear to be transcription errors during meiosis (cell division).
Remember, there are some people who are mosaics - and some have 46xx chromosomes in some cells, 46xy in others, not just anomalies in DNA strings, but whole chromosomes different.
And of course some viral infections can insert strands of DNA, and mutagens damage the replication at cell turnover. In hindsight, it should have been obvious that we should have been able to localise this damage one day in diseased tissue, we’ve known that it must occur for ages.
Thanks for the ping. I’m definitely going to keep my eye on this story!
But his son isn’t.
Thanks for the ping!
Sounds like a telomere breakdown which over 15 years would be inevitable. I suppose it would depend on the initial age of the cells selected for study. Or we all could be mutants....
Our family is affected by a disease called myotonic muscular dystrophy. In this disease, the 19th chromosone has a high repeat of CTG (I think) proteins. Normal repeats are 5 to 35. However, a high count can be unstable and increase.
This disease is anticipitory which means if a child receives the affected allele from a parent, the child will be more affected than the parent. The child’s CTG count will be higher than the contributing parent.
A Canadian researcher during a 2008 conference specifically stated that the repeats also increase during an affected person’s lifetime.
Exactly.
It is not gene expression we are talking about, it is actual base pair sequencing DNA differences.
Who knows? Maybe certain kinds of cells drop dna that has no use for that cell type.
This discovery is hugh. And series.
And might be one of the biggest shifts in genetic understanding since DNA itself was discovered.
....mutations happen. Why would a mutation in a specific gene during embryo development be any different?
Other folks get fired for surfin' the web at work. A little later Venter was forced out as president of Celera.Scientist Reveals Genome Secret: It's HimWhen scientists at Celera Genomics announced two years ago that they had decoded the human genome, they said the genetic data came from anonymous donors and presented it as a universal human map. But the scientist who led the effort, Dr. J. Craig Venter, now says that the genome decoded was largely his own. Dr. Venter also says that he started taking fat-lowering drugs after analyzing his genes... [M]embers of Celera's scientific advisory board expressed disappointment that Dr. Venter subverted the anonymous selection process that they had approved... Though the five individuals who contributed to Celera's genome are marked by separate codes, Dr. Venter's is recognizable as the largest contribution. He said he had inherited from one parent the variant gene known as apoE4, which is associated with abnormal fat metabolism and the risk of Alzheimer's, and that he was taking fat-lowering drugs to counteract its effects... Dr. Arthur Caplan, a biomedical ethicist at the University of Pennsylvania, said, "Any genome intended to be a landmark should be kept anonymous. It should be a map of all us, not of one, and I am disappointed if it is linked to a person."
Scientist Reveals Genome Secret: It's Him
by Nicholas Wade
April 27, 2002
The Neandertal EnigmaFrayer's own reading of the record reveals a number of overlooked traits that clearly and specifically link the Neandertals to the Cro-Magnons. One such trait is the shape of the opening of the nerve canal in the lower jaw, a spot where dentists often give a pain-blocking injection. In many Neandertal, the upper portion of the opening is covered by a broad bony ridge, a curious feature also carried by a significant number of Cro-Magnons. But none of the alleged 'ancestors of us all' fossils from Africa have it, and it is extremely rare in modern people outside Europe." [pp 126-127]
by James Shreeve
in local libraries
from page two:Hopping Up The Wrong Family TreeThe mitochondrial DNA method of analyzing mammals has turned on its head the common-sense approach of linking mammals by similar anatomical traits or "morphology," they say. Using a more comprehensive method to analyze the genetic material of 15 types of mammals, Duke researchers have shown that the mitochondrial DNA method that links disparate animals (hippo and whale, kangaroo and platypus) is statistically unreliable when it comes to evolutionary genetics, said Randy Jirtle, professor of radiation oncology at Duke University Medical Center. Their own research using nuclear genes (genes from the nucleus) has shown a nearly 100 percent statistical likelihood that the Duke results are correct.
July 2001
Popular Mechanics
Hopping Up The Wrong Family TreeSuch conclusive results led the researchers to strongly support the Theria hypothesis of classifying the three major groups of mammals. The Theria hypothesis holds that eutherians (humans, rats, pigs, whales, etc.) and marsupials (kangaroos, wallabies, koalas, etc.) have evolved from a common ancestor, and monotremes (platypus, echidna) have evolved from a different ancestor on a separate land mass. The mitochondrial method of studying evolution, however, supports the Marsupionta hypothesis, which places the platypus and kangaroo together. This controversy has lasted for more than two centuries since the discovery that the platypus lays eggs... "This is the first molecular evolutionary study that seriously and powerfully says the paleontologists have been right all along in grouping mammals the way they did," said Killian. "It turns out that common sense is correct."
July 2001
Popular Mechanics
Fathers can be influential tooBiologists have warned for some years that paternal mitochondria do penetrate the human egg and survive for several hours... Erika Hagelberg from the University of Cambridge, UK, and colleagues... were carrying out a study of mitochondrial DNAs from hundreds of people from Papua-New Guinea and the Melanesian islands in order to study the history of human migration into this region of the western Pacific... People from all three mitochondrial groups live on Nguna. And, in all three groups, Hagelberg's group found the same mutation, a mutation previously seen only in an individual from northern Europe, and nowhere else in Melanesia, or for that matter anywhere else in the world... Adam Eyre-Walker, Noel Smith and John Maynard Smith from the University of Sussex, Brighton, UK confirm this view with a mathematical analysis of the occurrence of the so-called 'homoplasies' that appear in human mitochondrial DNA... reanalysis of a selection of European and African mitochondrial DNA sequences by the Sussex researchers suggests that recombination is a far more likely cause of the homoplasies, as they find no evidence that these sites are particularly variable over all lineages.
by Eleanor LawrenceIs Eve older than we thought?"Two studies prove that the estimation of both when and where humanity first arose could be seriously flawed... The ruler scientists have been using is based on genetic changes in mitochondria, simple bacteria that live inside us and control the energy requirements of our cells. Mitochondria are passed from mother to daughter and their genes mutate at a set rate which can be estimated - so many mutations per 1,000 years... However, these calculations are based upon a major assumption which, according to Prof John Maynard Smith, from Sussex University, is 'simply wrong'. The idea that underpins this dating technique is that mitochondria, like some kinds of bacteria, do not have sex... Two groups of researchers, Prof Maynard Smith and colleagues Adam Eyre-Walker and Noel Smith, also from Sussex, and Dr Erika Hagelberg and colleagues from the University of Otago, New Zealand, have found that mitochondria do indeed have sex - which means that genes from both males and females is mixed and the DNA in their offspring is very different... Prof Maynard Smith and his colleagues stumbled over mitochondria having sex in the process of tracking the spread of bacterial resistance to meningitis... For the 'out-of-Africa' theory to hold water, the first population would have to have been very small. Sexually rampant mitochondria may put paid to this idea. Maynard Smith thinks that the origin of humanity is much older - may be twice as old - which, according to Eyre-Walker, means we are likely to have evolved in many different areas of the world and did not descend from Eve in Africa."
by Sanjida O'Connell 15th April 1999
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Thanks blam and LucyT. |
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Perhaps the methodology and conclusions may have to be adjusted?
I have no background to say.
(Apple of discord cast, running for cover.)
Cheers!
Thanks for the ping!
It’s not logical.
What about EVOLUTION do you fail to understand?
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