Table 6.

Lifetime risk of type 1 diabetes in first-degree relatives (proband diagnosed before age 20).1

RelativeRisk, %
Parents2.2 ± 0.6
Children5.6 ± 2.8
Siblings6.9 ± 1.3
 HLA-nonidentical sibling1.2
 HLA-haploidentical sibling4.9
 HLA-identical sibling15.9
Identical twin30–40
General population0.3