Board Change

Horizon Discovery Group plc

Board Change

Cambridge, UK, 12 November 2015: Horizon Discovery Group plc (LSE: HZD) ("Horizon" or "the Company"), the international life science company supplying genomics research tools and services that power genomics research and the development of personalized medicines, today announces that Dr. David Smoller is stepping down as Chief Business Officer and Executive Director of the Board, by mutual agreement and with immediate effect.

David joined Horizon as part of the Company's acquisition of Sage Labs in September 2014. A year on, with that acquisition now successfully integrated into the Company and performing well, it has been agreed that he will leave the Company to pursue other business interests.

Dr. Ian Gilham, Chairman of Horizon Discovery Group's Board of Directors commented: "The Board would like to thank David for his support over the past year in which he has assisted with the rapid integration of Sage Labs into the Horizon group and continued revenue growth of our Services business. We wish him every success in his future endeavours."

ENDS

For further information from Horizon Discovery Group plc, please contact:

Consilium Strategic Communications (Financial Media and Investor Relations)

Amber Fennell / Jessica Hodgson / Matthew Neal / Laura Thornton

Tel: +44 (0) 20 3709 5701

Email: [email protected]

Zyme Communications (Trade and Regional Media)

Katie Odgaard

Tel: +44 (0)7787 502 947

Email: [email protected]

Panmure Gordon (UK) Limited (NOMAD)

Corporate Finance: Freddy Crossley / Duncan Monteith / Fred Walsh

Broking: Tom Salvesen

Tel: +44 20 7886 2500

About Horizon Discovery Group plc www.horizondiscovery.com

Horizon is a revenue-generating life science group supplying research tools to organisations engaged in translational genomics research and the development of personalised medicines. Horizon has a diverse and international customer base of over 1,200 organisations across more than 50 countries, including major pharmaceutical, biotechnology and diagnostic companies as well as leading academic research centers. The Group supplies its products and services into multiple markets, estimated to total in excess of £29 billion by 2015.

Horizon's core capabilities are built around its proprietary translational genomics platform, a high-precision and flexible suite of gene editing tools able to alter almost any endogenous gene sequence of human or mammalian cell-lines. Horizon offers over 20,000 catalogue products, almost all of which are based on the application of gene editing to generate cell lines that accurately model the disease-causing mutations found in genetically based diseases. These 'patients-in-a-test-tube' are being used by customers to identify the effect of individual or compound genetic mutations on drug activity, patient responsiveness, and resistance, which may lead to the successful prediction of which patient sub-groups will respond to currently available and future drug treatments.

In addition, Horizon provides custom cell line and in vivo model generation services for research and bioproduction applications, quantitative molecular reference standards, in vivo disease models, and contract research and custom screening services.

Horizon is headquartered in Cambridge, UK, and is listed on the London Stock Exchange's AIM market under the ticker "HZD", for further information please visit: www.horizondiscovery.com.