By using genetic variations outside the MHC locus genes involved in type I interferon pathways, an animal study suggests that B- and T-cell methylation processes are associated with the development of both SS and SS-related lymphoma.[14] Excessive accumulation of B cells and plasma cells are presumed to produce abnormal antibodies in local microenvironments of SS-affected lacrimal glands. This evidence concerns the gene HLA-C and synovial sarcoma.