Skip to content

IEMbase 0622: PCYT1A-related retinoskeletal phosphocholine cytidylyltransferase deficiency

Scope

Field Value
IEMbase ID 622
Nosology 14.5.01.06
Gene PCYT1A
External IDs OMIM:608940; ORPHA:85167
Generated mapping UNMAPPED
Candidate DisMech targets None exact; Spondyloepiphyseal_Dysplasia_Congenita.yaml is a weak false candidate
Review date 2026-07-07

IEMbase phenotype signal

IEMbase represents the PCYT1A-related phosphocholine cytidylyltransferase 1A deficiency retinoskeletal phenotype, also named spondylometaphyseal dysplasia with cone-rod dystrophy / SMDCRD, as an autosomal recessive disorder with unknown treatability and no treatment rows.

The biochemical rows include decreased serum cholesterol, decreased plasma HDL cholesterol, and decreased serum triglycerides across age bands. Clinical and characteristic rows include retinopathy, short stature, spondyloepimetaphyseal dysplasia, cone-rod dystrophy, femoral bowing, and fractures.

DisMech phenotype coverage

No exact local PCYT1A or SMDCRD entry was identified. Spondyloepiphyseal_Dysplasia_Congenita.yaml is a skeletal-dysplasia name/phenotype neighbor, not a PCYT1A phosphatidylcholine-biosynthesis disorder with cone-rod dystrophy and hypolipidemia.

Concordance and completeness

Judgement: true local gap.

The later IEMbase PCYT1A lipodystrophy phenotype should be reviewed alongside this retinoskeletal phenotype, but this record is a distinct retinoskeletal presentation and should not be collapsed into an unrelated skeletal dysplasia.

Curation actions

  • Do not map to Spondyloepiphyseal_Dysplasia_Congenita.yaml.
  • Source-review PCYT1A phenotype splitting across retinoskeletal and lipodystrophy presentations.
  • Preserve hypocholesterolemia/low HDL/low triglyceride, cone-rod dystrophy, retinopathy, short stature, spondyloepimetaphyseal dysplasia, femoral bowing, and fracture prompts.