Muriel Wheldale Onslow

Muriel Onslow ( Wheldale; 31 March 1880 – 19 May 1932) was a British biochemist, born in Birmingham, England. She studied the inheritance of flower colour in the common snapdragon Antirrhinum and the biochemistry of anthocyanin pigment molecules. She attended the King Edward VI High School in Birmingham and then matriculated at Newnham College, Cambridge in 1900. At Cambridge she majored in botany. Onslow later worked within William Bateson's genetic group and then Frederick Gowland Hopkins' biochemical group in Cambridge, providing her with expertise in biochemical genetics for investigating the inheritance and biosynthesis of petal colour in Antirrhinum. She was one of the first women appointed as a lecturer at Cambridge, after moving to the Biochemistry department.

Education and personal life She was the only child of her parents John and Fannie (née Hayward) Wheldale. Her father was a solicitor. She attended King Edward VI High School in Birmingham, which was well known amongst single-sex schools for its strong science teaching to girls. In 1900, she entered Newnham College, Cambridge and achieved a First Class result in Part I of the Natural Sciences Tripos in 1902. She took Part II (Botany) in 1904 and again achieved a First Class result but was not awarded a degree since University of Cambridge did not award degrees to women until 1948.

In 1919 she married biochemist Victor Alexander Herbert Huia Onslow, second son of the 4th Earl of Onslow. They had no children. He had recently entered the field of chemical genetics, and their work was closely associated. Victor Onslow was paralysed from the waist down following a diving accident and died in 1922. In her memoir for her husband she wrote that he was a man of amazing courage and mental vitality enabling him to gain a career in biochemistry despite his physical circumstances, and with her encouragement and assistance.

By 1906, she had enough data to formulate a rudimentary factorial analysis on snapdragon inheritance. In 1907, Wheldale published a full explanation what became termed epistasis, the phenomenon of dominant-like relationship between different pairs of nonallelomorphic factors. Wheldale's study of genetics on flower coloration ultimately gained her the most recognition, with the 1907 publication of a full factorial analysis of flower colour inheritance in snapdragons and the four subsequent papers she published from 1909 to 1910. Her interest was in the biochemistry underlying the petal colours, rather than understanding inheritance itself. This application of chemical analysis to explain genetic data led to international recognition since it was among the first attempts at syntheses of these two areas.

She left Cambridge University between 1911 and 1914 owing to a studentship at the John Innes Horticultural Institution where, in addition to her laboratory work, she was valued as the Institution's leading botanical artist, able to capture the exact colours of plants. In 1913, she became one of the first three women to be elected to the Biochemical Society, after the society's initial exclusion of women in 1911.

She joined the biochemistry lab of Frederick Gowland Hopkins at Cambridge University in 1914, where she pursued the biochemical aspects of petal colour, whose genetics she had elucidated during her work with Bateson. She worked on oxidase systems which were also involved in additional areas of plant biology. This led her to work for the Food Investigation Board from 1917 onward and then, and from 1922 leading a team working on fruit ripening at the Cambridge Low Temperature Station from 1922.

Legacy There is a prize and research fellowship named after her at Newnham College, University of Cambridge.

Books by Muriel Onslow The Anthocyanin Pigments of Plants, 1916, revised in 1925 Practical Plant Biochemistry, 1920 Principles of Plant Biochemistry, Volume 1, 1931