IL4 and Autoimmunity: Autoimmunity has also been proposed as a pathogenic mechanism for DSP.23Interleukin-4 plays a key role in autoimmunity and acts as an anti-inflammatory;7it is a type of chemokine and cytokine, and it acts as a mediator of inflammatory or proinflammatory functions.6We did not observe statistical associations involving the IL-4 I3VNTR polymorphisms and DSP, but we observed lower mean values for conduction velocity in young with the A1A1 Q23 genotype (p = 0.02), suggesting a possible risk factor in this relationship.