Sep 09 2014

Has Jack the Ripper Finally Been Solved?

Jack the Ripper is perhaps the most iconic serial killer in history. Part of the mystique of this dark figure is the fact that he was never identified, leaving room for endless sleuthing and speculation. Every Ripper fan has their list of favorite suspects, usually filled with famous and powerful people of the time to add even more interest. My favorite, of course, is that he was a time-traveling friend of H. G. Wells.

Now a private researcher, Russell Edwards, claims that he has finally solved the case. First I will present his story without comment, and then we can take a skeptical look at it.

Edwards claims he acquired a blood-stained shawl in 2007 that is supposed to be from Catherine Eddowes, one of the five fairly accepted victims of the Ripper. The shawl was apparently recovered from the scene of Eddowes murder, and was covered in her blood. Acting Sergeant Amos Simpson took the shawl home as a gift for his wife. She was, apparently, not impressed and stored the shawl away without cleaning it.

The shawl remained in the possession of his family until they auctioned it off in 2007 and Edwards acquired it.

Edwards then solicited the help of Dr. Jari Louhelainen, a Finnish expert in historic DNA. Louhelainen found that the 126 year old shawl contained a great deal of blood, likely all from the victim. However, he also found a semen stain on the shawl. Genomic DNA is unlikely to have survived 126 years sufficiently intact for DNA matching. However, mitochondrial DNA is more hardy and likely did survive.

Sperm, however, contain few mitochondria (almost none). Fortunately, Louhelainen was able to isolate an epithelial cell from the region of the semen stain. Epithelial cells line many tissues, and so it is possible that the cell (which would contain mitochondrial DNA) was from the same source as the semen itself.

Louhelainen was able to extract and amplify the DNA, and then type it, finding that it belonged to the haplotype T1a1. This is a predominantly Eurasian mitochondrial haplotype, fairly rare in England and more common in northern Europe.

Mitochondria are passed down almost exclusively through the female line. Louhelainen had a Ripper suspect in mind – a “Polish madman” by the name of Aaron Kosminski. He was 23 at the time of the murders in 1888 and living in Whitechapel where they took place. About 3 years after the last known Ripper murder he was placed in an asylum, and he spent the rest of his life in asylums until he died at 53.

Kosminski has always been a suspect in the Ripper murders, although perhaps one of the less romantic ones. Louhelainen actually located a living female relative of Kosminski and found that she had the same mitochondrial haplotype as the sample from the semen stain on the shawl – a 100% match, according to Louhelainen.

Edwards and Louhelainen claim that this evidence ties Kosminski to Eddowes and her murder, and that therefore he is Jack the Ripper.

But wait…

The investigation of the shawl is certainly interesting, but it is unlikely to end debate over the identity of the Ripper. Here are the many problems that have already been pointed out by critics:

The provenance of the shawl is in doubt. It is, at the very least, an odd story that a police officer would gift his wife a bloody shawl from the scene of a gruesome murder. The bloody shawl was then passed down through the family and never washed.

Even if genuine, the shawl is problematic as evidence. It has been handled by many people over the years and is likely contaminated with many sources of DNA. Even at the time it was in the possession of Eddowes it likely was exposed to many sources of DNA. It’s even possible that Kosminski, who was known to frequent prostitutes in the area, contributed to the contamination even though he did not murder her.

Louhelainen’s analysis also has problems. He has not yet published his results in a peer-reviewed journal, so there are many details about the analysis we do not currently know. However, it does not appear that he tested alternate suspects as controls. It also does not appear that the analysis was performed with blinded samples, which is standard procedure in such cases.

Further, the mitochondrial DNA haplotype match does not point to a specific person, just an ethnic group. The match, therefore, can be a coincidence.


The mitochondrial DNA analysis of the samples from the shawl is certainly interesting science – it is cool that scientists can isolate DNA from such an old sample, amplify it millions of times, and then sequence it. No one at the time could have imagined such technology and that it would be able to finger a suspect.

The specific story of the Eddowes shawl and Kosminski, however, is problematic. Edwards and Louhelainen may have solved the case, but it is premature to conclude that they have. Science also operates by considering every possible problem with a line of evidence, and every possible alternate explanation.

Edwards and Louhelainen will have to deal with all of these (quite reasonable) objections to their conclusions before it is likely that their claims will be generally accepted. At the very least we should have independent replication with blinded samples and adequate controls.

Perhaps the greatest barrier that Edwards and Louhelainen face to the acceptance of their claims, however, is the fact that the Jack the Ripper story is much more compelling as an enduring mystery. If the mystery is solved, and the answer is unsurprising and mundane, that takes some of the wind out of the sails of this iconic narrative.

15 responses so far

15 thoughts on “Has Jack the Ripper Finally Been Solved?”

  1. Fair Persuasion says:

    Fact: Policeman more than 125 years ago brings home silk scarf for wife. Probably this was the acceptable way to obtain and store his evidence politely.
    Fact: Scarf never washed or worn by a female member of policeman’s family, respecting the man’s professional fascination with the murder.
    Fact: DNA samples are described as belonging to northern European stock. The other alleged suspects could have this type of DNA as intermarriages among humans occur regularly especially with conversions.
    Fact: Silk scarf is worn for Christian holidays.
    Fact: Delicate silk scarves are expensive more than 125 years ago. If left by the killer, the killer must be a man of means.
    Fact: The man accused in this forensic science project is an immigrant and mentally ill. Such characteristics as poverty and mental illness preclude access to luxury items. Instability on the job is common and creates a lack of resources.
    Fact: The possession and use of a knife blade is common to all suspects of that period. Frequently used for hunting purposes.
    Fact: A Christian killer would especially take offense at prostitutes at his holiday time. Violence in the name of his society and God would be condoned.
    Fact: Actions are by a male killer who is mentally disturbed by females on the street. Are there copy cat Ripper murders by more than one suspect?
    Fact: All females allow approach of killer with prospects of earning money for living. They are frequented by many males at the location.

  2. Kawarthajon says:

    “Acting Sergeant Amos Simpson took the shawl home as a gift for his wife. She was, apparently, not impressed”

    Steve, are you sure you’re not English? ‘Cause that is one of the best understatements I’ve heard in a while! Very funny!

  3. theconfuseddave says:

    “Sperm, however, contain few mitochondria (almost none). ”

    Wait, what? Did that come from the article, or from your own knowledge? Because either way, I’m pretty sure it’s not right. Sperm are basically nothing but a nucleus, a flagellum, and a ton of mitochondria to keep the flagellum beating for the day or so it takes them to get to the egg; relative to their cell size they have *masses* of mitochondria. They are all wiped out on fertilisation, but the sperm cells themselves are loaded with them.

    Unless all my university textbooks were lying to me. In which case, fascinating, got a reference for that?

  4. bachfiend says:

    It’s interesting, but highly circumstantial. A defence counsel would have a ball if this was the sole evidence against a dependent in a trial today. Even DNA results claiming that the odds of an exact match are, say, one in ten billion ( more than the Earth’s population) are bogus unless cross-contamination or the population group the sample originates are considered.

    Anyway. I wonder if a book is in the offing? Perhaps not. Usually the book comes first (along with the pay television special), then the research is published.

  5. Kawarthajon says:

    # bachfiend – you called it. Nicely done! The guy’s published a book:

    I read about this on the CBC new website:

    Check out a quote from the article:

    “I’ve spent 14 years working on it, and we have definitively solved the mystery of who Jack the Ripper was. Only non-believers that want to perpetuate the myth will doubt.”

    Ok, now I think the guy is full of it, talking about “non-believers”. What is this, a religion? I thought he was supposed to be doing science! Apparently he doesn’t want anyone disagreeing with him.

  6. slm says:

    I recall reading books by FBI profilers which were in part about working on the historical file in London. I believe they pegged Kosminski as well, but there is confusion as to which Kosminski. There could well have been two, one Nathan and one Aaron.
    I also have a lot of trouble with the long string of events that have to have occurred for the shawl to be good evidence, given that 126 years invites so many opportunities for contamination alone, nevermind swapping out or accidental washing up during spring cleanings. Let us assume it is the correct shawl. Even if it remained pristine as taken from her body, it appears Eddowes was a prostitute. Semen stains could quite plausibly relate to any of many men, as could epithelial cells. She worked an area famous as a criminal cross-roads, and in the day, it was filled with bars. I understood from general reading about the Ripper case that a great variety of men went through the area, including sailors and transient tradesmen. It appears that the area was one in which the “fairly unusual” Northern European man might be found, since population turnover appears quite high and the passers through would be from all over.
    If I were asked to take this case in for prosecution, I would not expect to win. The evidence is shaky and to me, no where near “beyond a reasonable doubt”. I’m not sure if it even makes the civil burden of “on the balance of probabilities”.
    I don’t know if that makes me a non-believer in Edward’s eyes, but as an experienced trial lawyer, I don’t buy it.

  7. dave – sperm have only a little mitochondria:

    That is why we inherit our mitochondrial DNA almost exclusively through the female line – it all comes from the ovum.

  8. theconfuseddave says:

    Uh, going to have to disagree with that article too. A little digging into the literature and the story is that male mitochondria are actively destroyed at fertilisation (actually, apparently soon after), NOT that sperm don’t have very many.

    This paper describes the elimination of the male mitochondria: – which at the very least indicates that there’s an active process going on, rather than just that sperm don’t have any.

    This paper also discusses the relationship between single-gender inheritance of mitochondria (i.e. the preference that all your mitochondria comes from one parent, usually your mother) and anisogamy (the tendency for the gametes, sperm and egg, to be morphologically different – usually with metabolically quiescent egg and metabolically very active sperm).

    As my research goes on, I think I’m spotting the issue that’s causing the confusion. I’m finding it extremely difficult to find a direct measurement on how many mitochondria are in a sperm cell (relative to their volume, since they are pretty tiny cells). Most of the time it seems to be discussed as measurement of mtDNA copy number, but that’s not a direct measurement of mitochondrial numbers. This paper: discusses quantifying mtDNA in sperm (and incidentally, finds it rather a lot higher than previous estimates, although strikingly much lower than in most other cells.

    To quote that last paper:

    “Our results are in accord with the previously described downregulation of mtDNA copy number during rat [41] and mouse and human [42] spermatogenesis. During the process of spermatogenesis, the mtDNA copy number is reduced a 5- to 6-fold (3850 to 700). This decrease in mtDNA copy number is likely regulated by a mitochondrial transcription factor A, which is also downregulated in mice and humans [41–43]. This phenomenon contrasts with and can appear paradoxical to the fact that sperm motility is a highly ATP-demanding process that clearly depends on mitochondrial oxidative phosphorylation activity. Other tissues or cell types increase their mitochondrial number and mtDNA content with higher ATP demands [21, 22, 26, 27]. Closer examination of the profound effects of spermatogenesis is needed to clarify the apparent paradox.

    !We have estimated from data published elsewhere [44, 45] that there is a 40-fold reduction in cell volume (from 1500 μm3 to 40 μm3) during spermatogenesis in parallel with a 5- to 6-fold reduction in mtDNA copy number. As a consequence of the cellular volume reduction, a 7-fold increase in mtDNA copy number per cubic micrometer of cell is concurrent with the higher ATP requirement during spermatozoon maturation. Thus, despite the decline of mtDNA per cell, mtDNA copy number per cell volume increases as the energy requirement for the spermatozoon increases.”

    It seems that mtDNA is massively downregulated (although not at all obliterated) during spermatogenesis; and the amount of paternal mtDNA that hits the egg is going to be dwarfed by that of the oocyte, even though relative to cell size they have mitochondria in spades. But yeah, can see that relative to the cellular mass of other types of tissue, it’d be harder to extract mtDNA from sperm.

    Sorry to be so pendantic, but I’ve heard you’re much the same way. 😉 (Also sorry for derailing a conversation about Jack the Ripper…)

  9. BillyJoe7 says:


    A quote from the article linked to by Steven Novella:

    “mtDNA, however, is derived almost exclusively from your mother. This is because the egg of a female human contains lots of mtDNA, while male sperm contains just a bit of mitochondria. One of the functions of a single mitochondrion is generating power for the cell that contains it, and sperm use a few mitochondria in the tail to power their race towards the egg for fertilization. These mitochondria are destroyed after the sperm fertilizes the egg”

    In other words, relative to the egg, the sperm contain few mitochondria and these are destroyed after fertilisation.
    Which is essentially what your references say as well.

  10. saschb says:

    Hi Dave,
    Although the adolescent in me appreciates the authors name in context to his topic, the review that you cite is pretty old. Here is a more recent one:

    And to cite that: “In humans, it was reported that motile sperm contained only 1.4 mtDNA molecules on average, which means that the majority of sperm probably do not contain any mtDNA (May-Panloup et al., 2003). This is similar to our results obtained in mice: the motile sperm contained only 1.29 mtDNA on average (Luo et al., 2013).” But you could argue that this is only referring to motile sperm (=mature sperm). The ejaculate contains a mixture of mature and immature sperm cells, thus the copy number of mtDNA should be a little bit higher there, I guess, because it seems that the pre-elimination of mt-DNA is already occurring at some point before fertilization. The paper, that you are citing, is reporting a 500-fold higher number for motile sperm, but I have some problems with this article. The biggest is that they don’t have a negative control for their Southern slot blot, which means, that we don’t know, if there is cross-hybridization with nuclear DNA, which could massively increase the numbers. Anyways, that paper is showing a number <<10000 for even immature spermatozoa (and 700 for mature), which is probably much too high, but compared to an egg cell with 10^6 it’s still negligible (as you already alluded to).

    The reason that many people (like me before reading this) don’t believe that there are (almost) no mitochondria in sperm cells is, that they think that you need mitochondria for ATP production. But at least some experts say that sperm cells produce their energy completely by glycolysis and you don’t need mitochondria for that. So no paradoxon there. (Im just wondering, what happens to all the pyruvate.) This seems to be a genuine on-going debate at the moment and I'm curious what will come out of it. Who would have thought that spermatogenesis could be this interesting…

  11. Fair Persuasion says:

    The “Polish Jew Theory” impacts both Aaron and Nathan. Historically England’s blatant fear of foreigners and Jews as outsiders must lead police or scientists, in this case, to assume Polish Jews more capable of vile acts in contrast to “pure blood Englishmen.” Illnesses such as gangrene or syphilis do not create angry men who specifically kill in defense of the moral doctrine of Christianity and its holidays.

  12. It always turns out to be more complicated.

    Delving into the specific issue of sperm mitochondria, it seems that this is more controversial than I thought, but that the notion that sperm contain few mitochondria is still basically correct.

  13. DLC says:

    Couple of quick additional points to amplify on :
    First, assuming the shawl was Eddowes’ (which I do not grant at this time), there is no cause to believe that the epithelial cell(s) left with the sperm sample come from Eddowes’ killer.
    She was, after all, a sex worker, employed in the business of having sexual relations with paying clients, and it is quite likely that one such client may have left a sample on her clothing earlier in the night of her murder.
    Second, I have to speak in reinforcement of Dr Novella’s point that the donor of the epithelial cell may be North European, but that does not mean he was Kosminski. It may well have been some other North European.
    Finally, taking both my points together, Kosminski may have paid for sex with Eddowes, and then left for parts unknown, leaving the field open to her real killer.

    I’ll also note that writer Patricia Cornwell has tried to use DNA testing to link a suspect to the ripper murders.

  14. Newcoaster says:

    I read this the other day, but then got bogged down in the nitpicky details of sperm mitochondria. However, after listening to the SGU discussion on my commute home today, I wondered did they attempt to match the blood to a descendent of Catherine Eddowes? They certainly went to a lot of trouble to get the semen sample potentially matched to their preferred killer. Did they try to prove the shawl could actually have been the murder victims?

    While that wouldn’t be conclusive, it would be a bit more compelling, given the complete lack of provenance and the unlikely chain of events that would have to happen for this to be true.

    And yeah…they are selling a book, not doing science.

  15. edwardBe says:

    The award winning documentary, “Amazon Women on the Moon” features a segment called, “Bullshit or Not? You decide” in which Henry Silva asks that question in reference to the proposal that Jack the Ripper was actually the Loch Ness monster in disguise. He neatly side steps presenting any motive that a sea (lake) monster might have for murdering London prostitutes, but it is an intriguing possibility…

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