The Montecarlo Exact Fisher Test demonstrated marked differences in all three Loci, DQA1, DQB1, DRB1 (p<0.0001) between AP versus both AITD and controls, as well as between AP type II (Addison's disease as major endocrine component) and AP type III (T1D + AITD).
A total of 300 consecutive and unselected patients with either PGA or monoglandular autoimmune thyroid disease (AITD) and 100 healthy control subjects were genotyped for the HLA class II DRB1, -DQA1, and -DQB1 alleles.
Dividing the APS collective into those with Addison's disease (APS type II) and those without Addison's disease but including type 1 diabetes and AITD (APS type III) demonstrated DR3-DQ2/DRB1*04:01-DQ8 as a susceptibility genotype in APS III (Pc<.001), whereas the DR3-DQ2/DRB1*04:04-DQ8 genotype correlated with APS II (Pc<.001).
The frequency of the DRB1*0405-DQB1*0401 haplotype was significantly higher in AITD patients with GAD Ab than in those without GAD Ab and control subjects.
The frequencies of DRB1 1101-DQB1 0301 and DRB1 1501-DQB1 0602 haplotypes were significantly lower in T1D patients with or without AITD than in control subjects.
Furthermore, the association of SUMO4 M55V variant was stronger in type 1 diabetic patients complicated with AITD (OR, 1.62; 95% CI, 1.06-2.47; P = 0.023) and in patients who have neither type 1 diabetes-susceptible class II HLA, DRB1*0405 nor DRB1*0901 (OR, 2.28; 95% CI, 1.34-3.87; P = 0.0018).