Mutations in the FTSJ1 gene coding for a novel S-adenosylmethionine-binding protein cause nonsyndromic X-linked mental retardation.
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.
Freude
Kristine
K
Max-Planck-Institute for Molecular Genetics, Berlin, Germany.
Hoffmann
Kirsten
K
Jensen
Lars-Riff
LR
Delatycki
Martin B
MB
des Portes
Vincent
V
Moser
Bettina
B
Hamel
Ben
B
van Bokhoven
Hans
H
Moraine
Claude
C
Fryns
Jean-Pierre
JP
Chelly
Jamel
J
Gécz
Jozef
J
Lenzner
Steffen
S
Kalscheuer
Vera M
VM
Ropers
Hans-Hilger
HH
D000328:Adult; D015152:Blotting, Northern; D002675:Child, Preschool; D041321:Chromosomes, Human, X; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D038901:X-Linked Intellectual Disability / Q000235:genetics*; D008780:Methyltransferases / Q000235:genetics*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics*; D010375:Pedigree; D017422:Sequence Analysis, DNA
D009687:Nuclear Proteins; C490101:FTSJ1 protein, human; D008780:Methyltransferases