Among Lincoln's unusual features were his asymmetric face and long limbs.
In order to prove his theory, Dr Sotos needed to find some of Lincoln's DNA, which was why he got in contact with Dr Ann Horsburgh, who works in the university's anatomy department, at the start of 2009 while she was living in California.
Dr Horsburgh, who normally retrieves DNA samples from prehistoric African material, said she was able to transfer her skills to searching for DNA on artefacts from Lincoln's assassination because "DNA is DNA", no matter what era it was from.
In the years since the start of 2009, she had attempted to retrieve DNA from a number of Lincoln "relics" in the university's anatomy department labs, including a piece of actress Laura Keene's blood-soaked dress, on which the president reportedly bled after he was shot by John Wilkes Booth, as well as a pillow and handkerchief.
Due to DNA's fragile nature, she had so far been unable to retrieve any DNA, which meant the project was in limbo until more artefacts could be sourced.
This would not be easy as "bits of dead presidents are hard to come by", she said.
However, because Lincoln was shot in the head and "head wounds bleed abundantly" there were "a lot of things" on which he was reported to have bled in the nine hours it took him to die, she said.
The best artefact for retrieving DNA would be something that had been stored in a cool, dry place.
Dr Horsburgh was still "cautiously optimistic" of finding traces of the syndrome in Lincoln's DNA and was far from giving up on the project.
The work Dr Horsburgh has done on the project featured on the National Geographic documentary called Lincoln's Secret Killer? aired in the United States last year.
Dr Jo-Ann Stanton, from the University of Otago anatomy department, has also been involved in the project.