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The MRC Toxicology Unit is sad to note the decease of Dr Martin Johnson a retired long-standing member of the Unit and British Toxicology Society.

Over many years Martin  meticulously investigated the target of some organophosphorus insecticides that cause degeneration of axons in the spinal cord and peripheral nerves.  This led to the selection of  insecticides less hazardous for human health and the identification of an esterase of unknown function, distinct from acetyl choline esterase, and termed Neuropathy Target Esterase. After much work by Martin and his colleagues this was identified as a novel esterase now known to be involved in phospholipid homeostasis. Subsequent research has shown that recessive  mutations in the gene for this esterase are associated with some rare human diseases.  Martin’s studies exemplified the approach that elucidating precise mechanisms of toxic action can have wider implications for  understanding fundamental physiology and  disease processes. Former colleagues of Martin in the Unit in Carshalton and  Leicester send their commiseration and best wishes to his family.