GWAS Data Have Identified Multiple Genes Associated with Autoimmune Diseases $\alpha$

GWAS data have identified multiple genes associated with autoimmune diseases. These data indicate the presence of polymorphisms in the gene sequence among the human population, where certain alleles are increased among patients with a particular autoimmune disease. One example is the gene encoding the IL-2R $\alpha$ chain. Interestingly, several of the polymorphisms in this gene that are found to be increased in patients with multiple sclerosis do not alter the protein coding sequence, and therefore do not result in differences in the amino acid sequence of the IL-2R $\alpha$ chain protein between healthy individuals and those with the disease-associated allele. Instead, it is likely that these allelic differences in the IL-2R $\alpha$ chain locus:

A) Alter the levels of expression or cell-type specificity of the IL-2R $\alpha$ chain protein
B) Are in sequences that affect a neighboring gene, rather than affecting the IL-2R $\alpha$ chain gene
C) Are associated with healthy versus autoimmune individuals, but do not play a causal role in disease incidence
D) Alter post-translational modifications of the IL-2R $\alpha$ chain protein, rather than the amino acid sequence
E) Affect the signal transduction proteins that need to associate with the IL-2R for intracellular signaling