Kathleen Gillespie, a molecular biologist interested in the mechanisms underlying autoimmunity leads the Diabetes Research Group at the University of Bristol, UK. She is Chief Investigator of the long-running Bart’s Oxford (BOX) family study of type 1 diabetes which has been recruiting children with type 1 diabetes and their families since 1985.  Studies of age-at-onset of diabetes have been a recurrent theme; she showed that HLA mediated susceptibility to T1D is decreasing over time with the most dramatic effects in children diagnosed under 5 years; that children with Down syndrome develop early onset type 1 diabetes; and that residual C peptide secretion is not observed in children in BOX diagnosed under 5 years.  A current focus is on why some children develop type 1 diabetes in the first few years of life while others who have the markers of ongoing islet autoimmunity are not diagnosed until adulthood.