DNMT3A and hereditary endocrine growth disease: In addition to the variants reported in patients with PGLs, germline gain-of-function DNMT3A variants located in the PWWP domain which cause widespread DNA hypermethylation at polycomb-regulated regions (with the H3K27me3 mark) have been found in patients with microcephalic dwarfism, an extreme growth disorder [16].