Lucien Cuenot

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Lucien Cuenot (1866-1951) was a French biologist. In the first half of the 20th century, Mendelism was not a popular subject among French biologists. However, one man, Lucien Cuenot, defied popular opinion and shirked the “pseudo-sciences” as he called them. Upon the rediscovery of Mendel's work by Correns, Devries, and Tschermak, Cuenot proved that Mendelism applied to animals as well as plants.

[edit] Cuenot’s experiments

Cuenot spent two years working on mice and came to the conclusion that three “mnemons” (genes) are responsible for the production of one “chromogen” or pigment and two “distases” enzymes. The pigment (if present) is acted upon by the enzymes to produce black or yellow colour. If no pigment is present the result is an albino mouse. Cuenot studied the offspring of various crosses between mice and concluded that these “mnemons” or genes were inherited in a Mendelian fashion.

Subsequently, Cuenot was the first person to describe multiple allelism at a genetic locus. He also described a lethal mutation in the mouse agouti locus at a time when such a mutation was unheard of.

[edit] A voice unheard

Cuenot’s pioneering work has afforded him little recognition to this day. William Bateson, the man credited the “one gene one enzyme” hypothesis never recognized Cuenot's discovery that certain traits arose due to the presence or absence of an enzyme. Archibald Garrod suggested in the early part of the 20th century that certain diseases occurred in the absence of an essential enzyme in a biochemical pathway and that these diseases were inherited as Mendelian recessives. Garrod failed to mention Cuenot in his work. At this time, there was widespread difficulty with reconciling genetics and biochemistry.

However Cuenot is in some ways responsible for his lack of acknowledgment. The symbolism he used in experiments described phenotype rather than genotype and were quite confusing. (Today’s crosses are described in terms of genotype). His studies on mice were also cut short when German troops invaded the town of Nancy, where he kept his mouse colony. After the war he never returned to his studies on mice and settled for the less controversial subjects of zoology and physiology.

[edit] Bibliography

Denis Buican, "Mendelism in France and the Work of Lucien Cuénot", Scientia, 1982, LXXVI, 117, 1-4, 129-137.