This domain family is found in eukaryotes, and is typically between 126 and 160 amino acids in length. The family is found in association with pfam05641, pfam00013. This family is the core C terminal region of the fragile X related 1 proteins FXR1P, FXR2 and FMR1. These different proteins have different regions at their very C-terminus. The Glutamine-arginine rich region facilitates protein interactions. This family contains two blocks of RGG repeats that bind to G-quartet sequences in a wide variety of mRNAs.