IEMbase 0492: PHKA2-related hepatic phosphorylase kinase alpha-2 subunit deficiency
Scope
| Field | Value |
|---|---|
| IEMbase ID | 492 |
| Nosology | 3.4.1.01 |
| Gene | PHKA2 |
| External IDs | OMIM:306000; ORPHA:264580 |
| Generated mapping | CANDIDATE; MEDIUM; Glycogen_Storage_Disease_Type_I.yaml |
| Candidate DisMech targets | Glycogen_Storage_Disease_Type_I.yaml |
| Review date | 2026-07-07 |
IEMbase phenotype signal
IEMbase represents X-linked PHKA2-related hepatic phosphorylase kinase alpha-2 subunit deficiency as glycogen storage disease type IXa. No treatments are listed. Biochemical rows include normal-to-increased ASAT/ALAT and biotinidase, decreased-to-normal phosphorylase kinase overall, decreased liver phosphorylase kinase, increased fasted plasma and urine ketones, normal-to-markedly increased liver glycogen, normal-to-increased cholesterol, low-to-normal fasting glucose, normal fasting plasma and urine lactate, normal-to-increased triglycerides, and normal plasma and urine uric acid. Clinical rows include doll-like adiposity, hypoglycemia, and short stature.
DisMech phenotype coverage
Glycogen_Storage_Disease_Type_I.yaml is not the correct target. It covers GSD
I due to G6PC1/SLC37A4 defects and autosomal recessive GSD Ia/Ib subtypes. It
does not model PHKA2, X-linked phosphorylase kinase deficiency, GSD IXa, or the
phosphorylase-kinase/liver-glycogen profile represented by IEMbase.
Concordance and completeness
Judgement: false-positive candidate; true PHKA2/GSD IXa local gap.
The candidate file is a carbohydrate-storage neighbor, but it is a different glycogenosis. IEMbase's disease is an X-linked hepatic phosphorylase kinase defect with relatively preserved lactate and uric acid, ketotic fasting hypoglycemia, liver glycogen storage, and short stature. The GSD I file's glucose-6-phosphatase mechanism and subtype structure do not provide exact coverage.
Curation actions
- Do not map this record to
Glycogen_Storage_Disease_Type_I.yaml. - Track PHKA2-related GSD IXa as a local curation gap.
- Preserve IEMbase prompts for X-linked inheritance, liver phosphorylase kinase activity, normal lactate/uric acid, ketones, short stature, doll-like adiposity, and biotinidase for a future exact entry.