Ketchum DNA Paper?

CMcMillan wrote:THIS IS WHAT WE ARE TALKING ABOUT BELOW:
mtDNA is generally passed un-mixed from mothers to children of both sexes, along the maternal line, or matrilineally

The issue certainly isn't as clear cut as you make it out to be and the presence of human mtDNA is by no means an indication that the DNA results are legitimate. If however they are legitimate then it should be possible to determine when any hybridisation may have occurred.

CMcMillan wrote:I was showing you how scientists were able to pinpoint Mitochondrial Eve via mtDNA which is "100% Human" and how it followed her up the chain to us. So I was clarifying your Confusion on HOW and Possibly WHY the mtDNA shows as 100% Human.

To begin with, the mitochondrial DNA of the samples (when it can be isolated) clusters with that of modern humans. That isn't itself a problem if we assume that those doing the interbreeding were human females, but the DNA sequences come from a variety of different humans—16 in total. And most of these were "European or Middle Eastern in origin" with a few "African and American Indian haplotypes." Given the timing of the interbreeding, we should only be seeing Native American sequences here. The authors speculate that some humans may have walked across the ice through Greenland during the last glaciation, but there's absolutely no evidence for that. The best explanation here is contamination.

As far as the nuclear genome is concerned, the results are a mess. Sometimes the tests picked up human DNA. Other times, they didn't. Sometimes the tests failed entirely. The products of the DNA amplifications performed on the samples look about like what you'd expect when the reaction didn't amplify the intended sequence. And electron micrographs of the DNA isolated from these samples show patches of double- and single-stranded DNA intermixed. This is what you might expect if two distantly related species had their DNA mixed—the protein-coding sequences would hybridize, and the intervening sections wouldn't. All of this suggests modern human DNA intermingled with some other contaminant.

The authors' description of the sequence suggests that it's human DNA interspersed with sequence from some other primate—hence the interbreeding idea. But the best way to analyze this would be to isolate the individual segments of non-human DNA and see what species those best align with. If the authors have done that, they don't say. They also don't mention how long the typical segment of non-human DNA is. Assuming interbreeding took place as the authors surmise, these segments should be quite long, since there hasn't been that much time to recombine. The fact that the authors don't mention this at all is pretty problematic.

Woodwose wrote:I think that article has been referenced a couple of times on this thread already. It just didn't generate much discussion and was sidelined.

Woodwose wrote:It was linked to and quoted by myself back on page 3, but no matter.

Woodwose wrote:I suppose there is also the possibility that the mtDNA is down to contamination, but the nDNA is from a species new to science. Although, wouldn't that mean that we should also find unknown mtDNA in the samples?

DPinkerton wrote:

Woodwose wrote:I suppose there is also the possibility that the mtDNA is down to contamination, but the nDNA is from a species new to science. Although, wouldn't that mean that we should also find unknown mtDNA in the samples?

I do not believe so...if that were the case...then everyone around today would not have homo sapien mtDNA...we would have mtDNA derived from the interbreeding of sapiens and neanderthal. The whole ability to track the lineage of a species is based on mtDNA staying consistent.

Scientists say they have recovered 60 percent of the genome so far and hope to complete it. By comparing that genome with those of various present day humans, the team concluded that about 1 percent to 4 percent of the genome of non-Africans today is derived from Neanderthals. But the Neanderthal DNA does not seem to have played a great role in human evolution, they said.

"So, if any hybridisation happened - it's difficult to conclusively prove it never happened - then it would have been minimal and much less than what people are claiming now," Manica says, in a statement.

However, a draft report headed by David Reich of the Harvard Medical School from the team that first reported the Neanderthal genes looks at differing rates of changes in the genes of both modern humans and Neanderthal samples and comes to a different conclusion. Based on their analysis, they estimate interbreeding did occur from 65,000 to 47,000 years ago, about the time that early modern humans are seen as leaving Africa.

DPinkerton wrote:I do not believe so...if that were the case...then everyone around today would not have homo sapien mtDNA...we would have mtDNA derived from the interbreeding of sapiens and neanderthal. The whole ability to track the lineage of a species is based on mtDNA staying consistent.

Woodwose wrote:

DPinkerton wrote:I do not believe so...if that were the case...then everyone around today would not have homo sapien mtDNA...we would have mtDNA derived from the interbreeding of sapiens and neanderthal. The whole ability to track the lineage of a species is based on mtDNA staying consistent.

My comment was prompted by the fact that our supposed hybridisation with Neanderthals comes from evidence that we share some of our nDNA with Neanderthals. We do not have any Neanderthal mtDNA in our genetic makeup.

Woodwose wrote:

DPinkerton wrote:I do not believe so...if that were the case...then everyone around today would not have homo sapien mtDNA...we would have mtDNA derived from the interbreeding of sapiens and neanderthal. The whole ability to track the lineage of a species is based on mtDNA staying consistent.

My comment was prompted by the fact that our supposed hybridisation with Neanderthals comes from evidence that we share some of our nDNA with Neanderthals. We do not have any Neanderthal mtDNA in our genetic makeup.

CMcMillan wrote:So how is it hard to not believe that Bigfoot has human mtDNA and NDA from something else.
Since this is what we have found with Neanderthal Hybridization

Squatchmaster G wrote:

CMcMillan wrote:So how is it hard to not believe that Bigfoot has human mtDNA and NDA from something else.
Since this is what we have found with Neanderthal Hybridization

Because of the varied human mtDNA found in the alleged Bigfoot samples, as I posted about recently in the thread.

The DNA from these three samples was sequenced using the next generation Illumina platform
at the University of Texas, Southwestern in Dallas, TX, a laboratory that sequences human
genomes 75-77. On average, there were 70-110 million total reads for each sample in each lane,
which is well over 90 Gb of raw sequence for each sample comprising greater than 30X
coverage.
The run summary generated by the HiSeq 2000 next generation sequencer provides scores, Q30,
for run quality 78 . Q30 can also be used to determine if there was any contamination (or mixture)
found in the samples sequenced. According to Illumina, a pure, single source sample would
have an Q30 score of 80 or greater with an average of 85. However, if there was contamination
present in the sample sequenced, the divergent sequences would compete against one another
prior to sequencing causing a contaminated sample to have a Q30 score of 40 to 50. The Q30
scores for the three genomes sequenced had Q30 scores of 88.6, 88.4 and 88.7 respectively for
samples 26, 31 and 140. The Q30 is the percent of the reads that have the statistical probability
greater than 1:1000 of being correctly sequenced. Therefore, not only were the sequences from a
single source, but the quality of the sequences were far above the average genome sequenced
using the Illumina next generation sequencing platform.

Author Contributions: M.K., P.W., D.S., A.H., S.B., R.S., and R.S. performed experiments.
M.K, and F.Z. analyzed the genetic data. M.K., A.W., and P.W. wrote and edited the manuscript.
A.H. analyzed and wrote the EM portion of the manuscript. D. S. analyzed and wrote the hair
analysis portion of the manuscript. D.T. analyzed and wrote the histopathology portion of the
manuscript. A.W. also researched pertinent additions to the manuscript and helped with data
collection. M.K. distributed samples, collected and combined data from the blind studies.

Woodwose wrote:Yes, I've read about the measures she has supposed to have taken. We can't just take her word for it though and the results and samples need to be independently verified.

Researchers who have been very meticulous regarding contamination can and do make mistakes, or overlook potential points of contamination.