Research Associate

Join a team of brilliant, passionate innovators determined to transform healthcare. At BillionToOne, we've built a category-defining, publicly traded company on Nasdaq where transparency fuels trust, collaboration drives breakthroughs, and every contribution moves the needle on our mission to make life-changing diagnostics accessible to all. We don't just aim for incremental improvements; we build products that are 10x better than anything that exists today.

Our scientists, engineers, sales executives, and visionaries are united by an unwavering commitment to changing the standard of care in prenatal and cancer diagnostics. This is where cutting-edge science meets human compassion, and every innovation you contribute helps remove the fear of the unknown from some of life's most critical medical moments.

If you're driven by purpose, energized by innovation, and ready to help shape the future of precision medicine at scale, this is where you belong.

The Research Associate position at BillionToOne is exceptionally rare at the undergraduate or early-career level. At BillionToOne, you will do much more than simply run routine protocols. Your work will have shape the development of high-impact molecular diagnostic products that are actively changing patient outcomes in both oncology and prenatal medicine. This is your chance to contribute to building novel molecular tests that help patients from day one.

You will work alongside and be mentored by scientists with interdisciplinary expertise across molecular biology, genomics, bioinformatics, and quantitative modeling. You will have the chance to use cutting-edge molecular techniques, next-generation sequencing, and robotic tools to move assays from research prototypes to analyzing thousands of real patient samples in our clinical lab as a commercially available product. Whether your ambition is to grow here at BillionToOne or ultimately pursue graduate studies, this position would be a solid foundation for your scientific career.

The Research Associate is an on-site position in our Menlo Park, CA office.

• Strong statistical and quantitative skills: You think rigorously about data. You understand the difference between signal and noise, appreciate the importance of statistical power, and bring quantitative reasoning to every problem.
• Meticulous attention to experimental detail: You understand that the quality of an experiment determines what we can learn from it. You keep rigorous records, design careful controls, and take pride in work that others can rely on and build upon.
• Ambition to make a difference now: You aren’t here to punch the clock. You want to understand why things work, push the boundaries of what’s known, and do what it takes to see your contributions show up in products that help real patients.

• →Design, execute, and troubleshoot experiments and assays under the guidance of Senior Scientists
• →Learn analytical and computational methodologies to analyze results under the guidance of Senior Scientists
• →Present scientific findings both verbally at group meetings and via internal written reports
• →Document experimental details and results
• →Collaborate with other teams to implement lab and bioinformatic workflows
• →Contribute positively to organizing and maintaining the R&D lab

• BS or MS in Bioengineering, Molecular and Cell Biology, Microbiology, Biophysics, Biochemistry, or related field
• 1–2 years of research experience (either during BS/MS or afterwards)
• Previous experience with standard molecular biology techniques (in particular, extensive experience with PCR, electrophoresis, DNA purifications)
• An ability to quickly learn mathematical, analytical, and experimental concepts
• High mathematical and statistical aptitude (e.g., you find the GRE math section to be extremely easy)
• Great attention to detail

• Start-up experience
• Knowledge of medical genetics
• Experience in a cell-free DNA setting
• Experience with next-generation sequencing library preparation
• Experience with computational analysis in R, Python, or other programming language

Unity Complete™ is the only non-invasive prenatal screen capable of assessing fetal risk for both common recessive conditions and aneuploidies from a single maternal blood sample. Our Northstar® liquid biopsy test uniquely combines treatment selection with real-time monitoring, giving oncologists unprecedented precision in cancer care.

From $0 to $150M+ in Annual Recurring Revenue in just five years. In 2025, we completed one of the most successful IPOs for a medical diagnostics company, building on nearly $400M in private funding,including our $130M Series D in 2024 and backed by world-class investors including Hummingbird, Adams Street Partners, Neuberger Berman, Baillie Gifford, and Premji Invest.

Forbes named us one of America's Best Startup Employers for 2025 and we're Great Place to Work certified, with 100% of our people willing to go the extra mile, even as we've scaled to over 700 employees.

Headquartered in Menlo Park with facilities in Union City, CA, and a new lab opening in Austin, TX in 2027, we're continuing to push the boundaries of what's possible in molecular diagnostics. We're just getting started.

Ready to help us change the world, one molecule at a time? Learn more at billiontoone.com