At the genetic level, several MGAT5 single-nucleotide polymorphisms (SNPs), associated with reduced expression of the MGAT5 enzyme, have been found to correlate with pathological changes in T cell glycosylation in chronic diseases such as IBD, COPD, and multiple sclerosis (MS) (47, 166, 167). This evidence concerns the gene MGAT5 and chronic obstructive pulmonary disease.