Other documents yet to be tested are two envelopes I believe were addressed and sealed by the Duke of Clarence, and an envelope of Queen Victoria's physician, Dr. William Gull. I do not believe that Druitt or any of these so-called suspects had a thing to do with murder and mutilation, and I would like to clear their names if I can. DNA testing will continue until all practical means are exhausted. The importance extends far beyond the Ripper investigation.
There is no one left to indict and convict. Jack the Ripper and all who knew him well have been dead for decades. But there is no statute of limitations on homicide, and the Ripper's victims deserve justice. And whatever we can learn that furthers our knowledge of forensic science and medicine is worth the trouble and expense. I was not optimistic we would set a DNA match, but I was surprised and quite crestfallen when the first round of testing turned up not a single sign of human life in all fifty-five samples. I decided to try again, this time swabbing different areas of the same envelopes and stamps.
Still, we came up with nothing. There are a number of possible explanations for these disappointing results: The one-billionth of a gram of cells in human saliva that would have been deposited on a stamp or envelope flap did not survive the years; heat used to laminate the Ripper letters for conservation destroyed the nuclear DNA; suboptimal storage for a hundred years caused degradation and destruction of the DNA; or perhaps the adhesives were the culprit.
The "glutinous wash," as adhesives were called in the mid-nineteenth century, was derived from plant extracts, such as the bark of the acacia tree. During the Victorian era, the postal system underwent an industrial revolution, with the first Penny Black stamp mailed on May 2, 1840, from Bath. The envelope folding machine was patented in 1845. Many people did not want to lick envelopes or stamps for "sanitary" reasons, and used a sponge. To add to the scientific odds against us when we swabbed envelopes and stamps, we could not possibly know who had licked their envelopes and who had not. The last genetic option left for us was to try a third round of testing, this time for mitochondrial DNA.
When one reads about DNA tests used in modern criminal or paternity cases, what is usually being referred to is the nuclear DNA that is located in virtually every cell in the body and passed down from both parents. Mitochondrial DNA is found outside the nucleus of the cell. Think of an egg: The nuclear DNA is found in the yolk, so to speak, and the mitochondrial DNA would be found in the egg white. Mitochondrial DNA is passed down only from the mother. While the mitochondrial region of a cell contains thousands more "copies" of DNA than the nucleus does, mitochondrial DNA testing is very complex and expensive, and the results can be limited because the DNA is passed down from only one parent.
The extracts of all fifty-five DNA samples were sent to The Bode Technology Group, an internationally respected private DNA laboratory, best known for assisting the Armed Forces Institute of Pathology (AFIP) in using mitochondrial DNA to determine the identity of America's Vietnam War Unknown Soldier. More recently, Bode has been using mitochondrial DNA to identify victims of the 9/11 terrorist attack on the World Trade Center. The examination of our samples took months, and while I was back in London's Public Record Office with art and paper experts. Dr. Paul Ferrara telephoned to tell me that Bode had finished the testing and had gotten mitochondrial DNA on almost every sample. Most of the genetic profiles were a mishmash of individuals. But six of the samples had the same mitochondrial DNA sequence profile component found on the Openshaw envelope.
"Markers" are locations. Markers in the Ripper/Sickert tests are where the base positions of DNA are located on the D loop sequence of the mitochondrial DNA - which is about as easy for most people to envision as it is for me to understand the mathematical equation for relativity, E = me2. An imposing challenge for DNA experts is to help the hoi polloi understand what DNA is and what test results mean. Posters showing matching fingerprints create a flurry of nods and "oh yes, I get it" looks from jurors. But the analysis of human blood - beyond its screaming fresh red or its old dark dried presence on clothing and weapons and at crime scenes - has always induced catatonia and pinpoint pupils in panicky eyes.
ABO blood-group typing was antenna-tangling enough. DNA blows mental transformers, and the hackneyed explanation that a DNA "fingerprint" or profile looks like a bar code on a soup can in the grocery store isn't helpful in the least. I can't envision my flesh and bones as billions of bar codes that can be scanned in a laboratory and come up as me. So I often use analogies, because I confess that without them I don't always comprehend the abstractions of science and medicine, even though I write about them for a living.
The swabbed samples in the Jack the Ripper case can be imagined as fifty-five sheets of white paper that are cluttered with thousands of different combinations of numbers. Most of the sheets of paper have smears, and illegible numbers, and mixtures of numbers that indicate they came from many different people. However, two sheets of paper each have a sequence of numbers that came from a single donor - or only one person: One sheet is James McNeill Whistler, and the other is a partial postage stamp on the back of a letter the Ripper wrote to Dr. Thomas Openshaw, the curator of the London Hospital Museum.
The Whistler sequence has nothing in common with any Ripper letter or any other non-Whistler item tested. But the Openshaw sequence is found in five other samples. These five samples are not single-donor, as far as we can tell at this point, and show a mixture of other base positions or "locations" in the mitochondrial region. This could mean that the sample was contaminated by the DNA of other people. A drawback in our testing is that the ever-elusive Walter Sickert has yet to offer us his DNA profile. When he was cremated, our best evidence went up in flames. Unless we eventually find a premortem sample of his blood, skin, hair, teeth, or bones, we will never resurrect Walter Richard Sickert in a laboratory. But we may have found pieces of him.
The clean single-donor sequence recovered from the partial stamp on the back of the Openshaw envelope is our best basis of comparison. Its sequence is the three markers, 16294 - 73 - 263, or the locations of DNA base positions in the mitochondrial regions - rather much as A7, G10, D12, and so on indicate places on a map. The five samples that have this same 16294 - 73 - 263 single-donor Openshaw sequence are the front stamp from the Openshaw envelope; an Ellen Sickert envelope; an envelope from a Walter Sickert letter; a stamp from a Walter Sickert envelope; and a Ripper envelope with a stain that tests positive for blood, but which may be too degraded to determine if it is human.
The results from the Ellen Sickert letter could be explained if she moistened the envelope and stamp with the same sponge her husband, Walter, used - assuming either one of them used a sponge. Or Sickert might have touched or licked the adhesive on the flap or stamp, perhaps because he mailed the letter for her.
Other samples contained one or two markers found in the single-donor Openshaw sequence. For example, a set of white coveralls that Sickert wore while painting had a mixture of markers that included 73 and 263. What is startling about this result is that there was a result. The coveralls are about eighty years old and had been washed, ironed, and starched before they were donated to the Tate Archive. I saw no point in swabbing around the collar, the cuffs, the crotch, and the armpits, but we did it anyway.