Cloned MRX Genes
| Year | MRX gene | Function | MRX mutation(s) | Reference |
| 1996 | FMR2 | nuclear protein; putative transcription activator | FRAXE families; deletion | Gecz et al. (1996) Gu et al. (1996) Gedeon et al. (1995) |
| 1998 | GDI1 | Rab GDP-dissociation inhibitor | MRX41; MRX48; MRX R | D'Adamo et al. (1998) Bienvenu et al. (1998) |
| 1998 | OPHN1 | Rho-GTPase activating protein | MRX60; t(X;12) | Billuart et al. (1998) |
| 1998 | PAK3 | p21 activated kinase | MRX30 MRX47 | Allen et al. (1998) Chelly (1999) |
| 1999 | RPS6KA3[i] | growth factor regulated kinase | MRX19 | Merienne et al. (1999) |
| 1999 | IL1RAPL | interleukin receptor accessory protein-like | MRX; deletions | Carrie et al. (1999) |
| 1999 | TM4SF2 | integrin associated protein | MRX | Zemni et al. (2000) |
| 1996 | DXS6673E[ii] | unknown | t(X;13) | van der Maarel et al. (2000) |
| 1999 | GRIA3[ii] | glutamate receptor AMPA type | t(X;12) | Gecz et al. (2000) |
[i] The only gene so far found to be involved in both syndromal (Coffin-Lowry syndrome) and nonspecific (MRX19) XLMRs.
[ii] Candidate MRX genes isolated from the X breakpoint of an X;autosome translocation and not yet found mutated in familial MRX.