13D Filing: Casdin Capital and Genmark Diagnostics Inc. (GNMK)

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Page 10 of 11 – SEC Filing

Exhibit A

AGREEMENT

The undersigned agree that
this Schedule 13D, dated March 27, 2018, relating to the Common Stock, $0.0001 par value of GenMark Diagnostics, Inc. shall be
filed on behalf of the undersigned.

March 27, 2018
(Date)

Casdin Capital, LLC

By: /s/ Eli Casdin

(Signature)
Eli Casdin, Managing Member
(Name/Title)

Casdin Partners Master Fund, L.P.

By: Casdin Partners GP, LLC, its general partner

By: /s/ Eli Casdin

(Signature)
Eli Casdin, Managing Member
(Name/Title)

Casdin Partners GP, LLC

By: /s/ Eli Casdin

(Signature)
Eli Casdin, Managing Member
(Name/Title)
/s/ Eli Casdin
Eli Casdin

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