This SNP has been linked to increased risk of adrenal insufficiency
However. there is mixed information regarding several other autoimmune diseases in a german population 
Promoter polymorphism rs3087456 in the MHC class II transactivator gene is not associated with susceptibility for selected autoimmune diseases in German patient groups.
[PMID 19605748] An evaluation of 4,000 UK RA patients did not show any risk associated with this SNP.
[PMID 20942939] A study of a Swedish cohort of 446 myasthenia gravis (MG) patients and 1866 controls found no significant association of the SNP with MG, either in the patient group as a whole or in any clinical subgroup.
[PMID 19317741] Autoimmune disease association signals in CIITA and KIAA0350 are not involved in celiac disease susceptibility
[PMID 20230522] Major histocompatibility complex class II transactivator gene polymorphism: associations with Löfgren's syndrome
[PMID 22272574] Influence of MHCIITA rs3087456 and rs4774 polymorphisms in the susceptibility to cardiovascular disease of patients with rheumatoid arthritis
[PMID 22461888] Interaction Analysis between HLA-DRB1 Shared Epitope Alleles and MHC Class II Transactivator CIITA Gene with Regard to Risk of Rheumatoid Arthritis
[PMID 22513452] CIITA gene variants are associated with rheumatoid arthritis in Scandinavian populations
[PMID 16318629] On the genetic involvement of apoptosis-related genes in Crohn's disease as revealed by an extended association screen using 245 markers: no evidence for new predisposing factors.
[PMID 16920747] MHC2TA promoter polymorphism (-168*G/A, rs3087456) is not associated with susceptibility to rheumatoid arthritis in British Caucasian rheumatoid arthritis patients.
[PMID 17012290] Role of the MHC2TA gene in autoimmune diseases.
[PMID 17075826] Investigation of the MHC2TA gene, associated with rheumatoid arthritis in a Swedish population, in a UK rheumatoid arthritis cohort.
[PMID 17678724] Environment-gene interaction in multiple sclerosis: human herpesvirus 6 and MHC2TA.
[PMID 17711409] A polymorphic variant in the MHC2TA gene is not associated with systemic lupus erythematosus.
[PMID 17875550] The MHC2TA -168A/G polymorphism and risk for rheumatoid arthritis: a meta-analysis of 6861 patients and 9270 controls reveals no evidence for association.
[PMID 19063739] Genomic NGFB variation and multiple sclerosis in a case control study.
[PMID 19221398] Chromosomal region 16p13: further evidence of increased predisposition to immune diseases.
[PMID 20211854] CIITA variation in the presence of HLA-DRB1*1501 increases risk for multiple sclerosis.
[PMID 21962857] Herpesvirus active replication in multiple sclerosis a genetic control?
[PMID 23133532] Polymorphisms in the Inflammatory Genes CIITA, CLEC16A and IFNG Influence BMD, Bone Loss and Fracture in Elderly Women
[PMID 23052709] Age-dependent variation of genotypes in MHC II transactivator gene (CIITA) in controls and association to type 1 diabetes
[PMID 23777927] Both qualitative and quantitative genetic variation of MHC class II molecules may influence susceptibility to autoimmune diseases: the case of endemic pemphigus foliaceus.