DNMT3B and myasthenia gravis: We also compared allele and genotype frequencies generated by the DNMT3B-579G>T polymorphism in MG patients stratified according to disease age at onset (≤45 years vs. > 45 years), to disease severity (less severe forms: Grade I + IIA vs. more severe forms: Grade IIB + III + IV), or to the presence/absence of associated autoimmune diseases (associated AID vs. no associated AID).