mitochondrial complex 2 deficiency, nuclear type 4
Findings
No curated finding names mitochondrial complex 2 deficiency, nuclear type 4 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
An autosomal recessive disorder due to pathogenic variants in the SDHB gene, resulting in Mitochondrial complex II deficiency and a variety of clinical manifestations, including neurological and muscular symptoms.
Definition from the Mondo Disease Ontology (MONDO:0030974), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Congenital onset · Infantile onset · Childhood onset
HPO, annotations 2026-09-02
Features
26 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Decreased activity of mitochondrial complex IIHPOHP:0008314
- 1 of 1 reported patient
- Delayed ability to standHPOHP:0025335
- 1 of 1 reported patient
- Delayed ability to walkHPOHP:0031936
- 1 of 1 reported patient
- Developmental regressionHPOHP:0002376
- 1 of 1 reported patient
- Elevated brain lactate level by MRSHPOHP:0012707
- 1 of 1 reported patient
- FallsHPOHP:0002527
- 1 of 1 reported patient
- Feeding difficulties in infancyHPO
Show the remaining 14
- Increased circulating lactate concentrationHPOHP:0002151
- 1 of 1 reported patient
- Increased circulating pyruvate concentrationHPOHP:0003542
- 1 of 1 reported patient
- Increased urine alpha-ketoglutarate concentrationHPOHP:0012402
- 1 of 1 reported patient
- IrritabilityHPOHP:0000737
- 1 of 1 reported patient
- LeukodystrophyHPOHP:0002415
- 1 of 1 reported patient
- Poor head controlHPOHP:0002421
- 1 of 1 reported patient
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- SDHBHGNC:10681
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2021
Where it sits
Other names
3 names
Resolves to: mitochondrial complex 2 deficiency, nuclear type 4
- Also called
- MC2DN4mitochondrial complex II deficiency, nuclear type 4SDHB-related Nuclear type mitocondrial complex II deficiency