FIG4 encodes FIG4 phosphoinositide 5-phosphatase (907 aa). Dual specificity phosphatase component of the PI(3,5)P2 regulatory complex which regulates both the synthesis and turnover of phosphatidylinositol 3,5-bisphosphate (PtdIns(3,5)P2). Highest expression in Artery Tibial (25.0 TPM) and Brain Frontal Cortex BA9 (22.9 TPM).

Charcot-Marie-Tooth disease type 4J is associated with mutations in the FIG4 gene on chromosome 6.

FIG4 is classified as a druggable target with score 0.0.

Genetic testing for FIG4 is available. Testing is considered confirmatory for diagnosis.

No approved treatments are currently available for Charcot-Marie-Tooth disease type 4J. An additional 1 compound holds orphan drug designation.

Orphan Drug Designations

While no drugs are FDA-approved specifically for Charcot-Marie-Tooth disease type 4J, some of the following designated compounds may be used off-label in clinical practice. Treatment decisions should be made in consultation with a specialist familiar with this condition.

The following drugs have received orphan drug designation from the FDA for Charcot-Marie-Tooth disease type 4J. Orphan designation reflects regulatory interest and does not indicate approval for treatment.

Estimated prevalence: <1 in 1,000,000 (VERY_RARE).

2 clinical trials registered, 2 recruiting. Interventions under study include other interventions and gene therapy. Pipeline includes 1 PHASE1. Research is sponsored by a mix of industry and academic institutions.

4 publications have been identified in PubMed for Charcot-Marie-Tooth disease type 4J. Research spans Review / Meta-Analysis (50%), Case Report / Case Series (25%), and Epidemiology / Natural History (25%).

Recent Publications

• Prasun P (2026). [PMID: 42170697](https://pubmed.ncbi.nlm.nih.gov/42170697/). *Clin Genet*. [Case Report / Case Series]

• Lauerova B (2025). [PMID: 41177402](https://pubmed.ncbi.nlm.nih.gov/41177402/). *Eur J Med Genet*. [Review / Meta-Analysis]

• Sadjadi R (2024). [PMID: 39133880](https://pubmed.ncbi.nlm.nih.gov/39133880/). *Neurology*. [Epidemiology / Natural History]

• Boura I (2024). [PMID: 39457468](https://pubmed.ncbi.nlm.nih.gov/39457468/). *Genes (Basel)*. [Review / Meta-Analysis]