Features include always present findings: Low muscle tone (hypotonia), Delayed ability to sit, Agenesis of corpus callosum, and Severe intellectual disability and others; and very common findings: Cerebellar hypoplasia. 51 total HPO annotations.

DPYSL5 encodes dihydropyrimidinase like 5 (564 aa). Involved in the negative regulation of dendrite outgrowth Highest expression in Brain Spinal cord cervical c-1 (157.7 TPM) and Brain Nucleus accumbens basal ganglia (54.8 TPM).

Ritscher-Schinzel syndrome 4 is associated with mutations in the DPYSL5 gene on chromosome 2.

DPYSL5 is classified as a druggable target with score 0.0.

Genetic testing for DPYSL5 is available. Testing is considered confirmatory for diagnosis.

Biomarker and diagnostic research for Ritscher-Schinzel syndrome 4 has been reported in the published literature.

Phenotype severity distribution: 7 always present features, 1 very common feature, 14 common features.

No clinical trials have been registered for Ritscher-Schinzel syndrome 4.

3 publications have been identified in PubMed for Ritscher-Schinzel syndrome 4. Research spans Basic Science / Preclinical (67%) and Diagnostic / Biomarker (33%).

Recent Publications

• Desprez F (2026). [PMID: 41286434](https://pubmed.ncbi.nlm.nih.gov/41286434/). *Molecular psychiatry*. [Basic Science / Preclinical]

• Singla A (2025). [PMID: 40448120](https://pubmed.ncbi.nlm.nih.gov/40448120/). *BMC medical genomics*. [Basic Science / Preclinical]

• Guo C (2025). [PMID: 40533793](https://pubmed.ncbi.nlm.nih.gov/40533793/). *European journal of medical research*. [Diagnostic / Biomarker]