Skip to comments.OU anthropologists reconstruct mitogenomes from prehistoric dental calculus
Posted on 04/17/2016 2:17:48 AM PDT by SunkenCiv
...In recent years, dental calculus has emerged as an unexpected, but valuable, long-term reservoir of ancient DNA from dietary and microbial sources... Very little dental calculus was required for analysis--fewer than 25 milligrams per individual. This makes it possible to obtain high quality genetic ancestry information from very little starting material, an important consideration for archaeological remains...
Although dental calculus preserves alongside skeletal remains, it is not actually a human tissue. Dental calculus, also known as tartar, is a calcified form of dental plaque that acquires human DNA and proteins passively, primarily through the saliva and other host secretions. Once mineralized within dental calculus, however, human DNA and proteins can preserve for thousands of years. Dental calculus thus serves as an important non-skeletal reservoir of ancient human DNA.
Conventional techniques for recovering ancient human DNA typically require the destruction of bone or tooth tissue during analysis, and this has been a cause of concern for many Native and indigenous communities. Dental calculus represents an important alternative source of ancient DNA that does not damage or disturb the integrity of skeletal remains. In addition, because dental calculus is the richest known source of DNA in the archaeological record, it presents unique opportunities for investigating archaeological sites with preservation challenges...
The demonstration that whole mitochondrial genomes can be reconstructed from small samples of dental calculus represents an important technological advancement for paleogenomic investigations in prehistoric North America and other regions where destructive analysis of skeletal remains is difficult or controversial.
(Excerpt) Read more at eurekalert.org ...
The Neandertal Enigma"Frayer'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
Wow. I had no idea.
Still, 25mg seems like a big quantity to find!
Maybe 25 mcg? Thats gotta be it.
Me either, but I failed calculus.
In a related story, a really tiny amount of gnome DNA is found in modern humans.
Neanderthals May Have Used Toothpicks
Thursday, April 14, 2016
YORK, ENGLAND—Anita Radini and a team of scientists examined Neanderthal teeth from Spains El Sidron Cave and found traces of bark trapped in fossilized plaque, or dental calculus, on some of them. According to a report in Live Science, the researchers say the wood, which had not been charred and was nonedible, may have come from the use of toothpicks or wooden tools held in the mouth as a “third hand.” Previous studies of Neanderthal teeth have found grooves that may have been made by toothpicks, and marks on teeth from El Sidron, found last year, suggest that these Neanderthals used them as tools. For more, go to “Decoding Neanderthal Genetics.”
Isn’t dental calculus counting when she smiles....to make sure she has a full set of teeth?
I got an A in calculus, but I failed at diligent dentist attendance.
A dentist friend of mine who goes to underdeveloped countries on summer missions trips, says that he is astounded at the big chunks of tartar he pries off of patients' teeth -- even young adults'...
speaking of things that didn’t happen:
Neanderthal Y chromosome offers clues to what kept us separate species
April 7, 2016
[snip] Three of those changes are missense mutations in genes known in humans to produce male-specific minor histocompatibility antigens. Antigens derived from one of these genes, known as KDM5D, are thought to elicit an immune response in some pregnant mothers against their male fetuses and lead to miscarriages. The researchers speculate that incompatibilities at one or more of these genes might have played a role in driving ancient humans and Neanderthals apart by discouraging interbreeding between them... The researchers say additional research is required... [/snip]
It’s a good idea to make denture she does!
Sunlight adaptation region of Neanderthal genome found in up to 65 percent of modern East Asian population
December 18, 2013
A baby aspirin that many take to lower the rate of heart disease contains 81 mg of aspirin plus binders and fillers. A gram contains 1000 mgs. A level teaspoon of sugar contains 5 grams. It is not hard to find 25 mg. of tartar on poorly cleaned teeth.
Neanderthals may have died of diseases carried by humans from Africa
Neandertals and Upper Paleolithic Homo sapiens had different dietary strategies
Wed, Apr 27, 2016
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