About Sihoun Hahn
Sihoun Hahn co-founded Key Proteo in 2019 and is its chief executive officer and chairman of the board. Key Proteo is a Seattle proteomic diagnostics company that works to expand newborn screening for treatable rare genetic conditions. Hahn also directs the Wilson Disease Center of Excellence and is an investigator at Seattle Children's Research Institute. A Seattle Children's article from October 2025 calls him Key Proteo's chief medical officer.
Hahn is a physician, laboratorian, academic researcher and professor with more than 30 years of experience. He began caring for Wilson disease patients as a fellow at the National Institutes of Health in 1990. He has held leadership and advisory positions at institutions that include the University of Washington and Seattle Children's Hospital. Those institutions also include the Washington State Department of Health's Newborn Screening program and the Wilson Disease Association. His team developed a way to measure ATP7B protein in dried blood spots. In summer 2025, the Washington State Board of Health voted to add Wilson disease to the state's newborn screening program.
Experience
This experience comes from official bios and from SEC filings. For roles taken from filings, the years are when the filings name Sihoun Hahn in the role, so the role may have started earlier or lasted longer.
Key Colleagues at Startups
The people Sihoun Hahn works with at each company, as listed on that company's latest Form D.
Sources
- SECKey Proteo, Inc. Form D, filed Oct 23, 2026
- companyKey Proteo — Announces New President and CEO (August 21, 2023)
- employerSeattle Children's — World's First Newborn Screening for Wilson Disease (October 1, 2025)
- governmentWashington State Board of Health — Newborn Screening TAC minutes, June 17, 2025