For decades, people who believe that Bigfoot is a real animal that lives in the hinterlands of North America have been waiting for proof of its existence. So, when a DNA diagnostics company published a press release on their website last week claiming to have sequenced the Bigfoot genome, it seemed too good to be true.
In the press release, DNA Diagnostics claimed that Texas veterinarian Melba Ketchum had sequenced the DNA of Bigfoot (aka Sasquatch). The company stated that the sequencing results confirm that Bigfoot exists and is a “novel hominin hybrid species...a human relative that arose approximately 15,000 years ago as a hybrid cross of modern Homo sapiens with an unknown primate species.”
So, do Bigfoot enthusiasts have reason to rejoice? Well, not just yet.
In response, the science blogosphere erupted with skepticism, and even ridicule, of Ketchum and her team. The press release is short on details and states that the study is still under peer review. So, no one can get a look at the actual data. Without that, it’s impossible to evaluate Ketchum’s claims.
According to the press release, Ketchum’s team sequenced 20 whole mitochondrial genomes and three whole nuclear genomes from “purported Sasquatch samples.” Their analysis allegedly found that Sasquatch’s mitochondrial DNA was identical to that of modern humans, but that the nuclear DNA was “a novel, unknown hominin” resulting from males of “an unknown hominin species” that contains “distinctly non-human, non-archaic hominin, and non-ape sequences.”
David Coltman, a geneticist with the University of Alberta, believes that plenty of caution is needed before interpreting this press release as proof of Bigfoot. “Until you see anything in peer review, there is nothing really to go by. And even if it does appear in a peer-reviewed journal, that doesn’t mean it’s true,” he said.
In 2006, Coltman and colleagues sequenced a supposed Bigfoot hair sample collected in Teslin, Yukon (1). The results showed it was just bison hair.
His biggest question about the new press release is how the hypothesized hybrid could possibly occur. “There’s a logical problem there, from a biology perspective. If Sasquatch is a hybrid between a primate more distant from the great apes and a human, their genomes would be incompatible. They wouldn’t be able to reproduce.”
So, what exactly might Ketchum have sequenced? Coltman doesn’t know for sure, but he said that it’s easy to pick up human mitochondrial DNA because of contamination, and that the nuclear DNA could represent environmental noise, more contamination of yeast, fungi, or other microorganisms–very common occurrences with any forensic sample. “There are big piles of DNA sequence that come out of any environmental sample that don’t line up to anything,” he said.
In the end, Coltman said that it’s next to impossible to prove that something doesn’t exist. Just because Ketchum’s DNA sequencing study may eventually prove to be bogus, an artifact of processing or contamination of the sample, doesn’t mean that there can’t be a Bigfoot out there somewhere, just waiting to be discovered–and its genome sequenced.
- Coltman, D., and C. Davis. 2006. Molecular cryptozoology meets the sasquatch. Trends in ecology & evolution 21(2):60-61.