Motor skills that had been learned may be lost, but generally the functioning of the brain and ability to think are not affected. [5] In MDDS associated with mutations in SUCLA2 or SUCLG1 that primarily affect the brain and muscle, hypotonia generally [en.wikipedia.org]

impairment ; Spasticity ; Strabismus Associated Genes SUCLA2 Mouse Orthologs Sucla2 (Withdrawn symbols: 4930547K18Rik ) Source OMIM:612073 (names, synonyms, disease associated genes), Orphanet (disease classes), HGNC, Ensembl, MGI (gene symbols, gene [mousephenotype.org]

It can also lead to the slowing down of thoughts and a reduction in physical movement, hearing impairment and seizures. [mirror.co.uk]

The disease also can cause hearing impairment and short stature. [mda.org]

The disease can cause the slowing down of thoughts and a reduction in physical movement, hearing impairment and seizures. [thesun.co.uk]

Dystonia ; Elevated serum creatine phosphokinase ; Facial diplegia ; Failure to thrive ; Feeding difficulties in infancy ; Generalized hypotonia ; Global developmental delay ; Hyporeflexia ; Infantile onset ; Intellectual disability, progressive ; Irritability [mousephenotype.org]

These may be accompanied by other problems such as irritability, loss of appetite, vomiting and seizures. There may be periods of sharp decline or temporary restoration of some functions. [umdf.org]

Other common problems that we see in our patients are poor bowel function, which often leads to either the irritable bowel disease or severe constipation. [mitochondrialdisease.nhs.uk]

[…] activity of mitochondrial respiratory chain ; Delayed gross motor development ; Dystonia ; Elevated serum creatine phosphokinase ; Facial diplegia ; Failure to thrive ; Feeding difficulties in infancy ; Generalized hypotonia ; Global developmental delay ; Hyporeflexia [mousephenotype.org]