Dr Tim Hearn

BSc (Birmingham), PhD (Cantab), MRSB, AFHEA

College Lecturer, Director of Studies, Postgraduate Mentor

College Roles

  • College Lecturer in Natural Sciences Biological
  • Director of Studies in Natural Sciences Biological (Plant Physiology, Parts II & III)
  • Postgraduate Mentor

University Roles

  • University Assistant Professor in the Department of Medical Genetics


Email: tjh70@cam.ac.uk


Dr Tim Hearn is an early career researcher who is an expert in both the genetics and physiology of circadian clocks. Dr Hearn is a comparative biologist, having studied circadian mechanism in humans, zebrafish and plants. He is recognised as an international authority on regulation of circadian clocks (Hearn and Webb 2020).

Dr Hearn studied for a BSc in Biological Sciences at the University of Birmingham, completing his undergraduate research project with Dr Juliet Coates, and was awarded the Farmer and Society of Biology Prizes for the highest degree in Biosciences. He subsequently moved to Cambridge and joined Professor Alex Webb’s laboratory as a PhD student, funded by an industrial CASE studentship in partnership with Bayer Cropscience (now BASF), to study the regulation of the circadian clock in plants. He was awarded the 2016 HE Woodmann prize for the best PhD thesis in plant science. He continued this work as a post-doctoral research associate, before moving to study the circadian clock in zebrafish with Prof David Whitmore. Dr Hearn now studies the circadian clock in humans and is an award nominated educator in the Department of Medical Genetics, taking a leading role in the Cambridge Genomic Medicine Programme (CGMP). His teaching focusses on bioinformatics and analysis of next generation sequencing data.

Research Interests

Dr Hearn runs the Comparative Chronomics research group. We discover how circadian clocks work in different species by taking a comparative biology approach. The Comparative Chronomics group is based in the Department of Medical Genetics at the University of Cambridge and collaborates with colleagues across multiple departments.

Chronomics is the study of time across the life span of an organism. We are interested in daily and seasonal time keeping mechanisms – circadian and photoperiodic oscillators. We utilise genomics, transcriptomics, metabolomics to make comparisons between systems.

We are especially interested in the usage of chronobiology in genomic medicine; for which we have coined the term “Chronomic Medicine”. Our goal is to investigate how chronobiology impacts human health and disease.

We are using the tools of genomic medicine to cement the idea of Chronomic Medicine – delivering mechanistic basis for the role of the circadian clock in the inheritance and phenotypes of rare disease and answering the community wide call to explore all potential aspects of circadian medicine.

We take several Masters students from the Cambridge Genomic Medicine Programme MPhil and MSt cohorts each year. Please get in touch to discuss a potential project. Dr Hearn encourages approaches from any clinicians who want to partner with us.

Recent papers

Fong CK, Hearn T, Webb SE, Frøland Steindal IA, Miller AL, Whitmore D. Daily rhythms in heartbeat rate are intrinsic to the zebrafish heart. Curr Biol. 2021 Mar 8;31(5):R239-R240. doi: 10.1016/j.cub.2021.01.106. PMID: 33689719.

Kroll F, Powell GT, Ghosh M, Gestri G, Antinucci P, Hearn TJ, Tunbak H, Lim S, Dennis HW, Fernandez JM, Whitmore D, Dreosti E, Wilson SW, Hoffman EJ, Rihel J. A simple and effective F0 knockout method for rapid screening of behaviour and other complex phenotypes. Elife. 2021 Jan 8;10:e59683. doi: 10.7554/eLife.59683. PMID: 33416493; PMCID: PMC7793621.

Hearn TJ, Webb AAR. Recent advances in understanding regulation of the Arabidopsis circadian clock by local cellular environment. F1000Res. 2020 Jan 27;9:F1000 Faculty Rev-51. doi: 10.12688/f1000research.21307.1. PMID: 32047621; PMCID: PMC6993837.