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Report: How the scientist who ‘unmasked’ Jack the Ripper made a ‘serious’ error

A letter allegedly written by Jack the Ripper and sent to a London news agency on Sept. 25, 1888, at a press preview of a museum exhibit in London on May 14, 2008. (AFP/Getty Images)

And so one of the West’s greatest, most enduring mysteries, which has spurred numerous failed attempts to crack it, continues. It’s the saga of Jack the Ripper, who committed at least five grisly murders in East London in the autumn of 1888 and then, poof, disappeared, never to be identified.

In the past 120 years, the rumor mill, an army of amateur sleuths and Britain’s lively hoax machine has circulated any number of names. It was believed the killer was a butcher or a doctor or even Queen Victoria’s grandson. Then attention settled on a guy named Robert Mann, a local morgue attendant. Or maybe it was Victorian artist Walter Sickert, who was “linked” — always the preferred verb in these cases — to several letters allegedly written by Jack the Ripper.

Nope, another sleuth said this go-around. It was actually a one-time suspect: Polish-born Aaron Kosminski, according to the author of a book that drew analysis from some non-peer-reviewed DNA testing. “The revelation puts an end to the fevered speculation over the Ripper’s identity which has lasted since his murderous rampage in the most impoverished and dangerous streets of London,” the Daily Mail confidently wrote in its “world exclusive.”

The debunking was largely the work of Britain’s Independent, an upscale, respectable rival to the sensationalist Daily Mail. It turned out the DNA evidence wasn’t nearly as iron-clad as the Mail made it out to be. The Mail claimed a shawl discovered at the murder scene of Ripper victim Catherine Eddowes contained her blood and the killer’s. The DNA from the shawl, the author said, was then linked to Eddowes through a living descendant named Karen Miller.

But closer scrutiny of the work has cast suspicion on it, according to the Independent. Researchers including Alec Jeffreys, who developed DNA profiling, say the original research made an “error in nomenclature.” And that error meant the DNA testing yielded traits extant in 99 percent of Europe’s population — rather than one specific person, the Independent said.

“They say the error means no DNA connection can be made between Kosminski and Eddowes,” the Independent reported, saying the error had been “serious.” “Any suggestion therefore that the Ripper and Kosminski are the same person appears to be based on conjecture and supposition — as it has been ever since the police first identified Kosminski as a possible suspect more than a century ago.”

If true, the error would cripple the latest of many blockbuster discoveries quickly taken down. One American explorer recently claimed he had found Columbus’s flagship vessel, the Santa Maria, only for a group of United Nations experts to refute that. Serious doubt was cast as well on a papyrus fragment written in Egyptian Coptic called the ‘Gospel of Jesus’s Wife’ that many now think is a fraud.

Some of the first to notice the error in the Jack the Ripper case were bloggers at “The best that can be said for such [a] match is that it doesn’t exclude Kosminksi from being the source of the DNA,” the blog wrote. “He could have left it, yes, but so could any one of hundreds of thousands, perhaps millions, of other people who share the same profile.”

The error in the DNA analysis, performed by Jari Louhelainen, may involve something as simple as getting the numbers wrong. “This DNA alteration is known as global private mutation (314.1C) and it is not very common in worldwide population,” Louhelainen wrote. ” … Thus, this result indicates the shawl contains human DNA identical to Karen Miller’s for this mitochondrial DNA segment.”

The problem, Jeffreys said, had to do with writing the mutation as “314.1C.” In the calculations, it really should have been written as “315.1c.” “Had Dr. Louhelainen done this, and followed standard forensic practice, he would have discovered the mutation was not rare at all but shared by more than 99 percent of the people of European descent,” the Independent reported.

So now, it looks like all the sleuths may still have their work cut out for them in identifying the Ripper. “One can only applaud those willing to take a scientific approach to the Jack the Ripper mystery,” wrote “But remember — the beauty of science is that it can be independently tested and verified. And as it stands now, [the] claims must be taken with a heavy dose of salt.”