Looking back: developments in our understanding of the genetic epidemiology of rheumatoid arthritis over the last 50 years.

The contribution of the arc Epidemiology Unit over its 50-yr history to the study of the genetic epidemiology of rheumatoid arthritis (RA) has been reviewed. Early family and population based studies carried out by John Lawrence were important in establishing the role of both genetic and environmental factors in determining susceptibility to RA. More recently, under the leadership of Alan Silman, population-based cohorts, twin- and family-based studies have formed the basis for an extensive programme of research aimed at identifying specific genetic factors that might influence susceptibility and outcome. A review of linkage and association studies is presented.