IEMbase 0761: DDHD1-related phosphatidic acid-preferring phospholipase 1 deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 761 |
| Nosology | 14.5.01.10 |
| Nosology code | IEM0670 |
| Gene | DDHD1 |
| External IDs | OMIM:609340; ORPHA:101008 |
| Generated mapping | UNMAPPED; weak candidate CALFAN_Syndrome.yaml |
| Candidate DisMech targets | None exact |
| Review date | 2026-07-08 |
IEMbase phenotype signal
IEMbase labels this autosomal recessive record as DDHD1-related phosphatidic acid-preferring phospholipase 1 deficiency, with alternate name autosomal recessive spastic paraplegia type 28. The phenotype rows emphasize adolescent and adult spastic paraparesis, nonprogressive cerebellar ataxia, chronic axonal sensorimotor polyneuropathy, basal ganglia abnormalities, intellectual disability, optic atrophy, cone-rod dystrophy, retinal dystrophy, and a brain iron row that is present in adolescence and adulthood and possible earlier.
DisMech phenotype coverage
No exact DDHD1 / SPG28 entry is present locally. The generated
CALFAN_Syndrome.yaml candidate is a false positive. CALFAN is an
SCYL1-related neurohepatic disorder with low-GGT cholestasis, recurrent liver
failure, cerebellar ataxia, and neuropathy; it does not cover DDHD1-related
phospholipase disease or SPG28 identity.
Other local spastic-ataxia or neuropathy entries provide phenotype context only and should not be treated as disease coverage.
Concordance and completeness
Judgement: true local gap.
The IEMbase record is specific for a DDHD1-associated hereditary spastic paraplegia. Shared ataxia, neuropathy, or imaging phenotypes are insufficient to map it to CALFAN or another different-gene disorder.
Curation actions
- Add a distinct DDHD1 / autosomal recessive spastic paraplegia type 28 target before treating this record as covered.
- Reject
CALFAN_Syndrome.yamlas exact coverage. - Preserve the retinal dystrophy, optic atrophy, basal-ganglia/brain-iron, polyneuropathy, cerebellar ataxia, and spastic paraparesis prompts.