Gamgee launches at YC S26 with AI-designed dog cancer vaccines

A Sydney data engineer whose viral March experiment on his dying dog now has a Y Combinator ticker. Paul Conyngham's startup Gamgee, part of the Summer 2026 batch, sequences a dog's tumor and healthy DNA, uses computational tools including ChatGPT and AlphaFold to identify the driver mutations, and manufactures a personalized mRNA vaccine designed to teach that individual dog's immune system what to attack, The Verge reports.

The origin story does the heavy lifting. Conyngham's rescue dog Rosie was diagnosed with advanced mast cell cancer in 2024. Surgery, chemo and immunotherapy all failed. He spent about $3,000 on tumor and healthy DNA sequencing at the University of New South Wales, partnered with UNSW's RNA Institute to manufacture the shot, and by mid-March the tennis ball sized tumor on Rosie's leg had shrunk by roughly 75% after her first injection in December. UNSW's Martin Smith raised the obvious follow-on: if this can be done for a dog, why not more broadly.

The economics are the real pitch. Industry estimates put manufacturing a personalized mRNA cancer vaccine at upward of $100,000 per patient, and a Jefferies analyst has projected around $200,000 per patient in the eventual human market. Dogs are a cheaper, faster proving ground. Gamgee lists Founders Fund, Y Combinator, Golden Gate Ventures, Atypical Ventures and the Doogood Foundation among its backers, alongside academic partnerships at UNSW and the University of Queensland.

The caution is coming from the experts themselves. Veterinary oncologist Justin Stebbing told reporters "we cannot be sure how much of Rosie's improvement is due to the vaccine, how long it will last, or whether the same approach would help other dogs." One dog is not a trial. Gamgee says it is recruiting veterinary oncologists and looking for funding to run a rigorous study, and no public source so far discloses what the company will charge pet owners or how many dogs are currently enrolled.

If the trial reads out cleanly, the more interesting story is not the pet market. It is that a small team running off-the-shelf LLMs, a protein modelling system and a roughly $3,000 sequencing workup can approximate the personalized-vaccine loop that well-funded pharma spends nine figures on. It slots into a run of tracked healthcare stories this quarter where AI-native teams push into workflows that used to belong to the big labs. QuantHealth's $45M raise to simulate clinical trials with AI last week is another example.