Associations between genotype and methylationvariance have been previously reported, for example at the putative metastable epiallelePAX8 (36) at the master regulatorof genomic imprinting ZFP57 (27) andat several probes in the major histocompatibility complex (MHC) region associated withrheumatoid arthritis (112). This evidence concerns the gene ZFP57 and Arthritis.