Researchers have identified a rare lineage of disease in Neanderthals that looks similar to what kills contemporary humans today.
The findings add to the growing understanding that the Neanderthals were capable of more than simple hunting and gathering, said study researcher Stéphane Luetge of the National Centre for Scientific Research in Grenoble.
“There’s a lot of similarity, but that’s really different from the analogues in today’s human population,” he said.
Luipper and colleagues analyzed microscopic characteristics of a Neanderthal skull found by British Natural History Museum researchers in March in a pile of artifacts collected in early 1991. The skull dates back about 100,000 years and was purchased for about £50 in an auction. Paleontologists used a dental technique, known as genotracheic compression, to determine the path taken by the mouth, tongue and throat to the teeth, giving the researchers a “digital signature” on one of the oldest pieces of human remains ever found.
The results matched those of other Neanderthal teeth analyzed by Brazilian scientists, whose analysis suggested the path taken from the mouth to the teeth was more or less linear. The Brazilian Neanderthal teeth were dated to about 80,000 years ago, according to a paper published in June in the journal Antiquity. The British fossil suggests the human technique took place 100,000 years ago.
“In terms of pathological origins, this is a good example,” said Kari Stefansson, a co-author of the study who was the first to study human teeth in a Neanderthal jawbone, during a Sept. 28 telephone interview from Reykjavik, Iceland. Stefansson, who co-founded the genealogical company deCODE genetics, discovered a Neanderthal disease called trichinosis in his specimens that relates to modern-day trichinosis.
All the Neanderthal teeth studied had plaque on their teeth that was confirmed as streptococcus, a bacteria linked to a range of infectious diseases. The more streptococcus the tooth harbored, the earlier the disease date, according to the team.
A single strand of streptococcus had been previously identified in two Neanderthal teeth, but further investigation led to the result. A closer look at the disease itself is needed, said Luetge, but it is clear from the details of their presence that it had evolved over thousands of years.
“It’s been happening even thousands of years ago,” he said.
Luipper and colleagues also reported Tuesday that current genetics technologies have the potential to prove their Neanderthal discovery correct. A team led by Sheila Shekman and Shannon Yochem of the University of Pennsylvania used a more traditional chemistry technique — carbon-13 dating — to determine the teeth’ age.
“That tells us that the trichinosis occurs today,” Luetge said.
The researchers created a DNA test called Glia Valencing, or GLaVal for short, that will allow the researchers to determine whether trichinosis is a current disease. When tissues are damaged, trichinosis causes three to four deadly infections that can affect parts of the body, in addition to the more noticeable red hair and ulcerated mouths, Shekman said.
“It has a surprisingly difficult life,” she said.
If the date on the tooth proves accurate, the study authors will likely begin to separate the genes from the bacteria. Eventually, doctors may be able to identify an individual with the disease, Shekman said. It is also possible it could become the subject of a new disease that doctors might be able to treat, since it’s so rare, she said.
Contact Rita Giordano at [email protected].