Tom Willis, Ph.D., serves as a Venture Partner at Illumina Ventures while also acting as CEO of Arima Genomics since. See sector focus and contact routes.
Tom Willis, Ph.D., serves as a Venture Partner at Illumina Ventures while also acting as CEO of Arima Genomics since June 2025. He invests in biotech and diagnostics companies from Seed to Series A stages, focusing on the San Francisco Bay Area and other major geos with a thesis rooted in genomics entrepreneurship. His typical check size ranges from $100,000 to $5 million, with a sweet spot around $1.5 million, and he has recorded at least one investment under his current position. Notable portfolio companies include Cernostics, Rebus Biosystems, and SonoThera, all reflecting his focus on genomic tools and cancer diagnostics. Willis brings over 20 years of genomics industry experience, having founded and exited ParAllele BioScience and Sequenta, and previously directed technology development at Stanford Genome Technology Center during the Human Genome Project. While no public writing or distinctive point of view is explicitly cited in available sources, his career demonstrates a consistent focus on translating structural mutation data into clinical cancer applications.
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