|Legal status||University Unit|
|Headquarters||The Keith Peters Building|
|Professor Judy Hirst|
|Medical Research Council|
The MRC Mitochondrial Biology Unit (formerly the MRC Dunn Human Nutrition Unit) is a department of the School of Clinical Medicine at the University of Cambridge, funded through a strategic partnership between the Medical Research Council and the University. It is located at the Addenbrooke’s Hospital / Cambridge Biomedical Campus site in Cambridge, England. The unit is concerned with the study of the mitochondrion, as this organelle has a varied and critical role in many aspects of eukaryotic metabolism and is implicated in many metabolic, degenerative, and age-related human diseases.
The Unit was founded in 1927 using a donation from Sir William Dunn, who left £1 million to charity on his death in 1912. Part of this money was used to fund what was then called the Dunn Nutritional Laboratory, with its research supported by the Medical Research Council (MRC). Its original research focus was to investigate the role of vitamins in human health. Under the directorship of Egon Kodicek this focus changed to more general nutritional research. The Unit was restructured in 1998 under the directorship of Professor Sir John Walker to focus on mitochondrial research. The Unit was renamed in 2009 to the Mitochondrial Biology Unit to reflect its mitochondrial expertise. In March 2017 the Unit was transferred from the MRC to the University of Cambridge. The current director of the Unit is Professor Judy Hirst.
The Unit has three major scientific aims:
The MBU is organised into nine independent research groups and includes 30-40 graduate students who are members of the University of Cambridge:
Professor Judy Hirst FRS (2020 - ) 
Professor Massimo Zeviani (2013 - 2019)
Professor Sir John Walker FRS (1998 - 2013)
Dr Roger Whitehead (1973 – 1998)
Dr Egon Kodicek CBE FRS (1963 - 1973)
Dr Leslie Harris (1929 - 1963)
Sir Frederick Gowland Hopkins (1927 - 1929)