To determine whether Dnmt3a was necessary for de novo methylation at genes associated with alternative T helper lineages, we performed whole genome enzymatic methylation sequencing (WGEM-seq) on WT and Dnmt3a KO (CD4-Cre) Tfh and Th1 cells sorted from LCMV infected mice at 7 days post infection. Here, DNMT3A is linked to infection.