AFF1 and cask-related x-linked intellectual disability: However, TENM1CRE, ARHGEF6CRE (Rac/Cdc42 guanine nucleotide exchange factor 6) and AFF2CRE (AF4/FMR2 family member 2) were observed in the gnomAD population and the latter two variants were also seen in hemizygous state suggesting that they were very unlikely to be a cause of XLID.