Type 1 diabetes is a multifactorial disease with both strong genetic and non-genetic components of disease susceptibility. The uniquely strong genetic risk factor region, the human leukocyte antigen region on chromosome 6p, contributes approximately half of the genetic component and can be used for screening for diabetes risk. For example, individuals with the highest risk compound heterozygote genotype comprise 2% of the general population, but have a twenty fold increased risk for type 1 diabetes with an absolute risk of approximately 7% by age 15 years.