IEMbase 0315: CTSD-related cathepsin D deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 315 |
| Nosology | 20.4.08.01 |
| Gene | CTSD |
| External IDs | OMIM:610127; ORPHA:228337 |
| Generated mapping | UNMAPPED |
| Candidate DisMech targets | Best fuzzy candidate Neuronal_Ceroid_Lipofuscinosis.yaml |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents CTSD deficiency as cathepsin D-deficient neuronal ceroid lipofuscinosis, also labeled CLN10. Characteristic rows include cerebellar atrophy, cerebral atrophy, congenital encephalopathy, abnormal EEG, epilepsy, microcephaly, movement disorder, muscular atrophy, spasticity, and vision loss or optic atrophy.
Additional clinical rows include ataxia, developmental regression, electron microscopy storage material, abnormal ERG, language difficulties, microcephaly, myoclonus, neurodegenerative disease, optic atrophy, pigmentary retinopathy, retinal dystrophy, seizures, abnormal somatosensory evoked potentials, spinal muscular atrophy, and abnormal VEP.
The biochemical signal is specific: cathepsin D is markedly decreased in dried blood spots, fibroblasts, and white blood cells. No treatment rows are present.
DisMech phenotype coverage
Neuronal_Ceroid_Lipofuscinosis.yaml includes CTSD as a definitive genetic
relationship for broad NCL and covers shared NCL features such as visual
impairment, retinal degeneration, cognitive impairment, seizures,
developmental regression, motor deterioration, myoclonus, and ceroid
lipopigment storage.
The local file does not provide a standalone CTSD/NCL10 disease or subtype. It also lacks CTSD enzyme-assay rows and the congenital encephalopathy, microcephaly, optic-atrophy, electrophysiology, and electron-microscopy detail present in IEMbase.
Concordance and completeness
Judgement: true missing standalone NCL10/CTSD target.
The broad NCL file is a useful disease-family context because the gene and core phenotype pattern are present. It is not sufficient as a precise canonical mapping for CTSD deficiency if downstream curation needs gene-specific CLN10 phenotype, enzyme, and diagnostic detail.
IEMbase adds a strong CTSD-specific biochemical prompt: cathepsin D deficiency across DBS, fibroblast, and WBC assays.
Curation actions
- Add a standalone CTSD/NCL10 target or explicit NCL umbrella subtype before treating this record as mapped.
- Consider source-backed cathepsin D enzyme-assay biomarkers during curation.
- Treat electron-microscopy storage material, congenital encephalopathy, microcephaly, optic atrophy, and electrophysiology rows as high-value review prompts.