This gene encodes a tRNA-modifying enzyme that acts as a dimethyltransferase, modifying a single guanine residue at position 26 of the tRNA. The encoded enzyme has both mono- and dimethylase activity when exogenously expressed, and uses S-adenosyl methionine as a methyl donor. The C-terminal region of the encoded protein has both a zinc finger motif, and an arginine/proline-rich region. Mutations in this gene have been implicated in autosomal recessive intellectual disorder (ARID). Alternative splicing results in multiple transcript variants encoding different isoforms. There is a pseudogene of this gene on the X chromosome.