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January 18, 2022

Sema4 to buy genomic testing firm GeneDx for $623M

YEHYUN KIM | CT MIRROR Sema4's Branford office.

Stamford’s Sema4 announced Tuesday it would buy genomic testing firm GeneDx of Maryland in a deal that projects $350 million in revenue for the combined companies this year. 

Sema4, a health intelligence company spun out of New York’s Mount Sinai Health System, signed a deal with Miami’s OPKO Health to buy GeneDx, a wholly-owned subsidiary based in Gaithersburg, Md.

The purchase price was $623 million, based on Sema4’s closing stock price as of Jan. 14, according to a company statement.

As part of the transaction, Sema4 said it had also entered into definitive agreements for a $200 million private placement of Sema4 Class A shares from a syndicate of institutional investors, including Pfizer. 

GeneDx specializes in rare disease diagnostic and exome sequencing services, with data on more than 300,000 clinical exomes, or the coding portions of genes, and over 2.1 million phenotypes. That data will bolster Sema4’s Centrellis health information platform and Traversa, its genomic analysis database.

Sema4 founder and CEO Eric Schadt said, “Adding GeneDx’s comprehensive dataset and capabilities to our offerings enables us to inform on an even broader range of diseases, further closing the gap between the practice of medicine and the availability of more clinically actionable guidance.”

The deal comes in the wake of Sema4's decision last month to pull back from COVID-19 testing after investments from Connecticut first lady Annie Lamont’s venture capital firm drew controversy.

Sema4 went public on the Nasdaq in July in a SPAC deal that valued the company at $2 billion. The company's stock debuted at $11.40 a share; it was trading at $4.06 a share as of Tuesday morning.

Contact Liese Klein at

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