The Somerton Man’s DNA – What’s Been Said

Much has been said and written by those with an interest in the Somerton Man’s DNA investigation, most of it lost in newspaper back-issues and internet forums, so we thought we’d fish a few out of the archives and present them here, in a fashion.

‘Based on everything I looked at in this case, I developed a hypothesis that the Somerton Man and Jo Thompson knew each other. They had a child, Robin Thomson. And if this is the case, then his daughter, Rachel is the granddaughter of the Somerton Man.’ (Derek Abbott)

‘He was also after my DNA. It’s probably the first request I’ve had for a man to do that.’ (Rachel Egan)

‘Something just magically drew us together. By the following day we had decided we were going to get married. It all happened remarkably fast.’ (Derek Abbott)

‘Rachel having Thomson DNA is inexplicable without more hard information, but TSM himself being a Thomson would make a lot of sense. I believe I read somewhere that a Carl Thompsen was proposed as the TSM, but not much in depth research done about that lead. Spellings were not consistent before the 20th century.’ (Matthew Kleid)

‘In later years, she had told me that she was always grateful to George because he married her when she was pregnant, even though he wasn’t the father. I remember her telling me that George wasn’t the father of Robin.’ (Greg O’Leary, friend of Jo Thomson) ..  Note: they were married in 1950, well after the birth of Robin.

‘So the plaster cast, embedded in the cast are hairs. So I thought to myself perhaps we can extract DNA from these hairs. We managed to get some hairs. We were only able to extract two percent of the amount of DNA that we really need to form an identification. We needed much higher concentration levels, which we could do with the Somerton man’s teeth or his ear bone, for example.’ (Derek Abbott) 

‘I think Mitochondrial DNA testing of the hair samples from the plaster bust of SM stands a reasonable chance of identifying close relatives of SM.’ (Byron Deveson)

‘More recently, (Rachel Egan’s DNA) links were also found to the grandparents of the man that Jo Thomson eventually married.’ (Colleen Fitzpatrick, Forensic Genealogist))

‘So my head is spinning.‘ (Derek Abbott)

‘DNA phasing and a chromosome browser should make it possible to pinpoint where on the Thomson tree Rachel Egan is inheriting Thomson DNA. It’s not that hard and an amateur can do it. I am not normally cynical, but I think they know more information and just not telling us. Professor has kept mum before about some things.’ (Matthew Kleid)

‘Prof. Abbott’s team have recovered about 2% of SM’s autosomal DNA from the hair samples. There is a brief summary of the findings thus far at:
https://projectswiki.eleceng.adelaide.edu.au/projects/index.php/Projects:2019s1-141_CSI_Adelaide:_Who_killed_the_Somerton_Man%3F#Chromosome

Two notable findings are: “Ethnicity check via GEDmatch shows that he was North Atlantic for a proportion of more than a quarter of the chart. The second largest section shows that he was Baltic, which does not stray too much from North Atlantic region.’ (Byron Deveson)

‘We don’t need the Somerton Man’s DNA. Rachel Egan has it, a quarter precisely. I don’t believe for a second there is a reasonable chance TSM is NOT her grandfather. The concordance of facial features is said to be like winning the lottery. Here’s another uncanny coincidence that one of the proposed identities is a man named Carl Thompsen? Spellings were not necessarily consistent in the 19th century.’ (Matthew Kleid)

There needs to be public interest reasons that go well beyond public curiosity or broad scientific interest for the Attorney-General to approve an exhumation.” (SA Premier Raus. 2018. Labor)

“For more than 70 years, people have speculated who this man was and how he died,” South Australia Attorney General Vickie Chapman said. Last month Ms Chapman said the decision to exhume the body followed “intense public interest” in the case. (SA Attorney General Chapman. 2021. Liberal)

‘Today is phenomenal. It’s a credit to the SA police force that they’ve managed to get the approval for this exhumation. I’ve been working and studying this case since about 2007. There’s so many strange things about it that nothing about it ever surprises me anymore.’ (Derek Abbott)

‘I’m a forensic DNA specialist. So I have a particular interest in using DNA to identify unknown human remains, in particular compromised human remains that are either very old or very degraded. I would be very confident that after 70 years, we would likely be able to recover some DNA. So yes, I would like to see this case resolved, as I would all of our unresolved, unidentified remains cases in Australia. There are a number of limitations with the Somerton Man case, and they particularly relate to the fact that we don’t have many reference samples for comparison. So we do have the alleged granddaughter. But my understanding is that the son was cremated. But I definitely think it’s worth trying.’ (Associate Professor Jodie Ward, NSW Health Pathology and UTS.)

‘There’s a long-running mystery that’s been going on now for over 70 years. You have a body on a beach of an unknown man and I may have some sort of connection to the case. The Somerton case for Derek is an obsession. He’s fascinated with it and I think he always will be.’ (Rachel Egan)

“The relationship had moved very quickly, and she (Roma Egan) was worried that Professor Abbott had married her daughter for her DNA, even though she had already agreed to let him use it.” (ABC Australian Story, November 2019)

In December 2017, Derek Abbott announced three “excellent” hairs “at the right development stage for extracting DNA” had been found on the plaster cast of The Somerton Man, and had been submitted for analysis to the Australian Centre for Ancient DNA at the University of Adelaide. Processing the results could reportedly take up to a year. In February 2018, the University of Adelaide team obtained a high definition analysis of the mitochondrial DNA from the hair sample from Somerton Man. They found that he and his mother* belonged to haplogroup H4a1a1a, which is possessed by only 1% of Europeans.

‘Hair contains very much more mitochondrial DNA than nuclear DNA and DA’s team has already extracted mtDNA from SM’s hair and shown that SM’s mitochondrial DNA belongs to the H haplogroup (as does mine H1ag1) and Derek recently told me (below) that his team are hoping to refine the haplogroup (sub-clade) data. If his team are successful in this, then it is just a matter of time before SM is identified.’ (Byron Deveson)

The grandparents of Prosper were: Hugh Thomson 1839-1906 and Ann May nee MacTaggart 1846 – (?) on Prosper’s paternal side, and Benjamin Hawkes 1851-1934 and Alice nee Fortune 1850-1895 on his mother’s side. So, the connection could be through any one of these four.

The bottom line is that  the DNA connection doesn’t necessarily come from the Thomson line. I note that the other three other possible perps have robust family trees and the DNA connection could come from Roma’s side. (Byron Deveson)

‘It really should be possible for Rachel Egan to reconstruct her grand-paternal family tree in this day and age, just by web sleuthing, and from there identify a missing relative. Also, there should be someone still living with memories of the Somerton Man, but we do not have long. Evoking my personal experience once again, I was able to connect recently with the 95 year old sister of my great-grandmother on whom I had the least information. She was a total cipher and there is no web information about her at all. My guess is the Somerton Man was estranged from his family as well and left few to no public records. So time is of the essence here.’ (Matthew Kleid)

“Does that prove she’s (Rachel) not connected now to the Somerton man? Or does that prove that somehow the Somerton man is related to her assumed grandfather?’ (Derek Abbott)

‘We could go really crazy, what if it’s something stranger.
e.g. Prosper and Jess are half-siblings to the Thomsons and SM is the father.’ (Someone)

Finally.

‘I essentially think about him every day and I wonder every day, literally, about the truth and where I fit into all this and where he fits into all of this and how we fit into all of this as a family.’ (Rachel Egan)