Mutations in the FTSJ1 gene coding for a novel S-adenosylmethionine-binding protein cause nonsyndromic X-linked mental retardation
Freude, Kristine × Hoffmann, Kirsten Jensen, Lars-Riff Delatycki, Martin B des Portes, Vincent Moser, Bettina Hamel, Ben van Bokhoven, Hans Moraine, Claude Fryns, Jean-Pierre Chelly, Jamel Gécz, Jozef Lenzner, Steffen Kalscheuer, Vera M Ropers, Hans-Hilger #
American Journal of Human Genetics vol:75 issue:2 pages:305-9
Nonsyndromic X-linked mental retardation (NSXLMR) is a very heterogeneous condition, and most of the underlying gene defects are still unknown. Recently, we have shown that approximately 30% of these genes cluster on the proximal Xp, which prompted us to perform systematic mutation screening in brain-expressed genes from this region. Here, we report on a novel NSXLMR gene, FTSJ1, which harbors mutations in three unrelated families--one with a splicing defect, one with a nonsense mutation, and one with a deletion of one nucleotide. In two families, subsequent expression studies showed complete absence or significant reduction of mutant FTSJ1 transcripts. FTSJ1 protein is a homolog of Escherichia coli RNA methyltransferase FtsJ/RrmJ and may play a role in the regulation of translation. Further studies aim to elucidate the function of human FTSJ1 and its role during brain development.