Mendel Medal 2019 – Professor William G. Hill
Photograph : Anne-Katrin Purkiss
Professor Laurence Hurst awarded the 2019 Mendel Medal to Professor William G. Hill, University of Edinburgh.
Bill Hill was one of the world’s leading quantitative geneticists, with a distinguished research career spanning 40 years, focused on the variability in complex traits arising from the joint effects of genetic and environmental factors. Raised on a Hertfordshire farm (that the family still owns), Bill came into genetics via an interest in livestock improvement. After studying Agriculture at Wye College London and Genetics at UC Davis, Bill moved to Edinburgh to undertake a PhD in quantitative and population genetics with Alan Robertson. Apart from occasional periods abroad to work with his many collaborators, he has stayed in Edinburgh since, building on the historical strength in quantitative genetics developed by Douglas Falconer, Alan Robertson and others.
Bill’s research was primarily theoretical, using mathematical and computer models of the behaviour of genes in populations to understand the genetic basis of quantitatively varying traits. His contributions have included studies of how genetic variation is maintained in natural populations, and how selection (both natural and artificial) changes the structure of genetic variation. He made numerous very influential advances in our understanding of the effects of finite population size and mutation on variability and selection responses, notably the role of mutation in maintaining continued responses to selection. In addition to his purely scientific work, Bill made many important contributions to the application of genetics to animal improvement that have had a major impact on the livestock breeding industry. Bill was a sought-after consultant by both public agencies and private businesses in this area.
Of especial importance was been his work on linkage disequilibrium, the non-random associations between genetic variants at different sites in the genome. Such associations now provide an immensely important tool for geneticists seeking to map and identify genes involved in disease and other complex traits, and Bill’s work provided a basic framework for modelling and analysing linkage disequilibrium that he went on to apply to genetic mapping. As a PhD student with Alan Robertson, Bill demonstrated how selection acting at a locus interferes with that happening simultaneously at linked loci. The Hill-Robertson effect has become one of the most influential ideas in population genetics, finding a new lease of life in its ability to explain patterns of molecular evolution and diversity revealed by the genomic revolution. Within recent years, Bill’s work helped to shape our understanding of what genome-scale data sets can tell us about complex traits and relatedness within populations.
Bill served with distinction in several important academic administrative posts, culminating in the position of Dean of the Faculty of Science and Engineering at the University of Edinburgh until his official retirement in 2002. Until illness took hold in 2019, Bill continued to be highly active in the fields of quantitative genetics and animal breeding and inspired many generations of scientists through his teaching and supervision. Bill was elected to the Royal Society of Edinburgh in 1979, the Royal Society of London in 1985 and appointed OBE in 2004, in part for his contribution to the UK animal breeding industry. Bill was also an honorary member of the Genetics Society for many years. Bill felt unable to present his medal lecture at the “Century of Genetics” conference in Edinburgh during November 2019, but nevertheless attended while Trudy MacKay spoke to a packed theatre about his work, highlighting reminiscences and accolades from colleagues, ex-students and friends that the Society compiled into a downloadable booklet. Sadly, Bill died toward the end of 2021.