Karim studied Natural Sciences at the University of Cambridge, before moving to Oxford as a PhD student with Paul Nurse. Subsequently, Karim spent periods as a postdoctoral fellow with Sergio Moreno in Salamanca, Stephen Kearsey in Oxford and John Diffley in London. In 2001, Karim started his group at what is now the Cancer Research UK Manchester Institute. Karim was selected to join the EMBO Young Investigator Programme in 2004, and in 2010 Karim was elected a member of EMBO and received the Hooke medal from the British Society for Cell Biology.

Karim moved as Professor of Genome Integrity to Dundee in 2013 and was elected a fellow of the Royal Society of Edinburgh in 2016. In addition to his research, Karim serves as ‘Head of Sustainability and Climate Action’ for the School of Life Sciences.”