[PMID 18694972] People with the human leukocyte antigen (HLA) genotype DRB1*0301-DQA1*0501-DQB1*0201/DRB1*04-DQA1*0301-DQB1*0302 (more simply known as "DR3/4-DQ8") are at the highest risk of developing type-1 diabetes.
The rs2040410(A) allele is associated with DRB1*0301, and the rs7454108(C) allele is associated with DQB1*0302.
Instead of more traditional antibody-based tests, two SNPs (rs2040410 and rs7454108) can be used to identify the presence or absence of the DR3/4-DQ8 genotype and thus the highest-risk heterozygous genotype associated with type-1 diabetes. For users of Promethease, this is determined via Gs121.
Separately, rs2040410 is associated with type-1 diabetes and systemic lupus erythematosus (SLE). Nature
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[PMID 19143810] Haplotype-based search for SNPs associated with differential type 1 diabetes risk among chromosomes carrying a specific HLA DRB1-DQA1-DQB1 haplotype.
[PMID 19143815] MHC fine mapping of human type 1 diabetes using the T1DGC data.
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