multiple mitochondrial dysfunctions syndrome 4
Findings
No curated finding names multiple mitochondrial dysfunctions syndrome 4 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Any fatal multiple mitochondrial dysfunctions syndrome in which the cause of the disease is a mutation in the ISCA2 gene.
Definition from the Mondo Disease Ontology (MONDO:0014611), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Infantile 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.
- Absent speechHPOHP:0001344
- 6 of 6 reported patients
- Decreased activity of mitochondrial complex IHPOHP:0011923
- 1 of 1 reported patient
- Optic atrophyHPOHP:0000648
- 6 of 6 reported patients
- Very frequent (80% to 99% of cases)
- SpasticityHPOHP:0001257
- 6 of 6 reported patients
- Appendicular spasticityHPOHP:0034353
- Very frequent (80% to 99% of cases)
- Developmental regressionHPOHP:0002376
- 4 of 6 reported patients
- Very frequent (80% to 99% of cases)
Show the remaining 14
- Decreased activity of mitochondrial complex IIHPOHP:0008314
- Occasional (5% to 29% of cases)
- Decreased activity of mitochondrial complex IVHPOHP:0008347
- Occasional (5% to 29% of cases)
- DystoniaHPOHP:0001332
- Occasional (5% to 29% of cases)
- Elevated brain glycine level by MRSHPOHP:0034893
- Occasional (5% to 29% of cases)
- Elevated brain lactate level by MRSHPOHP:0012707
- Occasional (5% to 29% of cases)
- HyperglycinemiaHPOHP:0002154
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.
- ISCA2HGNC:19857
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2020
- Strong · Genomics England PanelApp · Autosomal recessive · 2020
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Moderate · Ambry Genetics · Autosomal recessive · 2018
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
3 names
Resolves to: multiple mitochondrial dysfunctions syndrome 4
- Also called
- fatal multiple mitochondrial dysfunctions syndrome caused by mutation in ISCA2ISCA2 fatal multiple mitochondrial dysfunctions syndromemultiple mitochondrial dysfunctions syndrome type 4