DPH1 encodes diphthamide biosynthesis 1 (438 aa). Catalyzes the first step of diphthamide biosynthesis, a post-translational modification of histidine which occurs in elongation factor 2. Highest expression in Pituitary (88.4 TPM) and Brain Cerebellum (80.8 TPM).

Developmental delay with short stature, dysmorphic facial features, and sparse hair 1 is associated with mutations in the DPH1 gene on chromosome 17.

The DPH1 protein participates in DPH6 ligates ammonium to diphthine-EEF2, DPH2 transfers a 3-amino-3-carboxypropyl group from AdoMet to residue 715 of nascent EEF2, and Synthesis of diphthamide-EEF2 pathways.

DPH1 is classified as a druggable target (Enzyme category) with score 2.7.

Genetic testing for DPH1 is available. Testing is considered confirmatory for diagnosis.

Phenotype severity distribution: 13 always present features, 4 common features.

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

No clinical trials have been registered for developmental delay with short stature, dysmorphic facial features, and sparse hair 1.

4 publications have been identified in PubMed for developmental delay with short stature, dysmorphic facial features, and sparse hair 1. Kisho has analyzed 3 by research type. Research spans Case Report / Case Series (67%) and Review / Meta-Analysis (33%).

Recent Publications

• Al-Ajlouni YA (2025). [PMID: 41444928](https://pubmed.ncbi.nlm.nih.gov/41444928/). *Journal of medical case reports*. [Case Report / Case Series]

• Waskow ER (2025). [PMID: 39166428](https://pubmed.ncbi.nlm.nih.gov/39166428/). *American journal of medical genetics. Part A*. [Review / Meta-Analysis]

• Gowda VK (2025). [PMID: 40130534](https://pubmed.ncbi.nlm.nih.gov/40130534/). *American journal of medical genetics. Part A*. [Case Report / Case Series]