Replication studies were carried out in two groups of cases and control as well as 2,319 affected sib-pair families previously recruited and characterized by the T1DGC6. The British cases were from the JDRF/WT DIL, and the controls were drawn from the British 1958 Birth Cohort, and the UK Blood Service controls of the WTCCC. The second set of cases and controls from Denmark were recruited from a nationwide registry. All cases (49% females) were diagnosed before age 18 years and the mean age at onset 9.02 years. Control subjects were randomly selected from the Inter99 study22.
