FTSJ1 encodes FtsJ RNA 2'-O-methyltransferase 1 (329 aa). Methylates the 2'-O-ribose of nucleotides at positions 32 and 34 of the tRNA anticodon loop of substrate tRNAs. Requisite for faithful cytoplasmic translation. Highest expression in Cells Cultured fibroblasts (48.7 TPM) and Cells EBV-transformed lymphocytes (37.9 TPM).

Intellectual disability, X-linked 9 is associated with mutations in the FTSJ1 gene on chromosome X.

FTSJ1 is classified as a druggable target (Enzyme category) with score 0.0.

Genetic testing for FTSJ1 is available. Testing is considered confirmatory for diagnosis.

Biomarker and diagnostic research for intellectual disability, X-linked 9 has been reported in the published literature.

Phenotype severity distribution: 3 always present features, 7 common features.

No clinical trials have been registered for intellectual disability, X-linked 9.

132 publications have been identified in PubMed for intellectual disability, X-linked 9. Kisho has analyzed 89 by research type. Research spans Basic Science / Preclinical (29%), Epidemiology / Natural History (22%), and Review / Meta-Analysis (16%).

Recent Publications

• Richards M (2026). [PMID: 41913263](https://pubmed.ncbi.nlm.nih.gov/41913263/). *Cardiol Rev*. [Epidemiology / Natural History]

• Semyachkina AN (2026). [PMID: 41917976](https://pubmed.ncbi.nlm.nih.gov/41917976/). *J Med Case Rep*. [Case Report / Case Series]

• Pan X (2026). [PMID: 41764152](https://pubmed.ncbi.nlm.nih.gov/41764152/). *J Mol Med (Berl)*. [Basic Science / Preclinical]

• Yska HAF (2026). [PMID: 41650360](https://pubmed.ncbi.nlm.nih.gov/41650360/). *Neurology*. [Diagnostic / Biomarker]

• Babu A (2026). [PMID: 41190569](https://pubmed.ncbi.nlm.nih.gov/41190569/). *J Pediatr Ophthalmol Strabismus*. [Epidemiology / Natural History]

• Boeri S (2026). [PMID: 41724124](https://pubmed.ncbi.nlm.nih.gov/41724124/). *Epilepsy Behav*. [Case Report / Case Series]

• Li J (2026). [PMID: 41986485](https://pubmed.ncbi.nlm.nih.gov/41986485/). *Eur J Pediatr*. [Diagnostic / Biomarker]

• Liu N (2026). [PMID: 40884535](https://pubmed.ncbi.nlm.nih.gov/40884535/). *J Magn Reson Imaging*. [Epidemiology / Natural History]

• Wright MA (2026). [PMID: 40696909](https://pubmed.ncbi.nlm.nih.gov/40696909/). *J Child Neurol*. [Review / Meta-Analysis]

• Guerrero-Gonzalez JM (2026). [PMID: 42063232](https://pubmed.ncbi.nlm.nih.gov/42063232/). *Brain Behav*. [Case Report / Case Series]