Senior Data Scientist

BillionToOne is a next-generation molecular diagnostics company dedicated to developing powerful and accurate diagnostic tests that are accessible to all. Our innovative QCT molecular counting technology significantly enhances the resolution of disease detection using cell-free DNA by over a thousandfold. This groundbreaking technology is integral to our product offerings, including one of our flagship products, Unity Complete™ , the only non-invasive prenatal screen capable of assessing fetal risk for both common recessive conditions and aneuploidies from a single maternal blood sample. Leveraging the same molecular counting technology, we've expanded our impact into oncology in 2023 with a pioneering liquid biopsy test, Northstar, that combines treatment selection with monitoring. To date, over 500,000 patients have benefited from our innovative and precise diagnostic tests , and our Annual Recurring Revenue (ARR) has grown from $0 to $125 million in the last ~4 years.

BillionToOne has successfully raised close to $400 million in funding, with a notable $130 million Series D round completed in June 2024, resulting in a company valuation of over $1 billion. This funding has come from prestigious global institutional investors, including Hummingbird, Adams Street Partners, Neuberger Berman, Baillie Gifford, and Premji Invest. BillionToOne has recently been recognized by Forbes as one of America's Best Startup Employers for 2024 , highlighting the company's exceptional work environment and commitment to innovation.

Our team has grown significantly and we now proudly employ over 400 highly skilled individuals. Despite substantial growth, we have successfully maintained the unique culture that has defined BillionToOne from inception, continuing to cultivate a team that is not only diverse and passionate but also innovative. Headquartered in Menlo Park, California, with an additional facility in Union City, California, BillionToOne remains at the forefront of significant advances in molecular diagnostics, evidenced by the recent announcement of clinical outcomes data for its Unity Fetal Risk Screen and new advancements in cancer diagnostics. For more detailed information about BillionToOne and its groundbreaking work, please visit our website at .

We are currently looking for a high-performing Data Scientist to join our team and lead our Prenatal clinical data initiatives as we scale the company by growing over 300+% YoY.

We are seeking a highly skilled and motivated Senior Data Scientist to join our team. This role is integral to advancing our research initiatives, optimizing processes, and supporting key business decisions through data-driven insights. The ideal candidate will have a strong background in data science, experience with clinical data, and proficiency in using AI tools to streamline and enhance our data analysis processes.

Key Responsibilities:

Clinical & Lab Data Utilization & AI Integration:

• Leverage various clinical data sources to build tools that answer key clinical questions.


• Work with clinical affairs to manage and interpret clinical data to support research publications in medical journals.


• Collaborate with the research team to optimize AI prompts and run AI-powered chart reviews, ensuring efficient and HIPAA-compliant data handling.


• Support the development and implementation of AI-driven solutions to improve data processing and analysis.


• Assist in the migration of the outcomes database to Salesforce, ensuring accurate data transfer from the Data Warehouse.


• Build new tables in the data warehouse to facilitate querying of clinical data


• Build queries and Tableau dashboards to support key clinical and commercial decisions.

• Work closely with the lab team and data warehouse personnel to automate data analysis around lab processes.


• Build and provide support for databases used for lab assay monitoring


• Work closely with stakeholders to answer key business questions using data from across the organization, providing insights that drive decision-making.


• Develop and maintain dashboards and reports that provide actionable insights to the team.

Required Qualifications:

• Excellent communication skills and ability to work collaboratively with cross-functional teams.


• PhD in a Bioscience related field.


• Strong experience in Python and data manipulation tools (e.g., SQL, R).


• Ability to retrieve and munge data from disparate sources and formats


• Experience with clinical data.


• Proficiency in using AI tools to enhance data processing and analysis.


• Strong problem-solving skills and ability to troubleshoot complex queries.

Preferred Qualifications:

• Strong understanding of bioinformatics


• Knowledge of data warehousing and ETL processes.


• Experience with data visualization tools such as Tableau.


• Experience with AWS (S3, Batch) and Airflow


• Minimum 1-2 years of experience as a data scientist or related field and willingness to learn new topics


• Familiarity with Clarity and other clinical data management systems.

Benefits And Perks:

• Working with a team of ‘rockstars’ who bring out the best in everyone


• Open, transparent culture that includes weekly Town Hall meetings


• The ability to indirectly or directly change the lives of hundreds of thousand patients


• Multiple medical benefit options; employee premiums paid 100% of select plans, dependents covered at 80%


• Extremely generous Family Bonding Leave for new parents (16 weeks, paid at 100%)


• Retirement savings program including a 4% Company match


• Free daily on-site lunches provided from top eateries


• Latest and greatest hardware (laptop, lab equipment, facilities)


• A variety of perks on campus (state of the art gym, restaurant)


• Free on-site EV charging (compatible with all EVs, including Tesla)

At BillionToOne, we are proud to offer a combination of (1) competitive base pay, (2) the opportunity for professional growth, and (3) industry leading company benefits (free healthcare options, 401k match, very generous fully paid parental leave etc.).

For this position, we offer a total compensation package of up to $220,000 per year, including a base pay range of $155,000-$175,000 per year.

BillionToOne is an equal opportunity employer. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.