The clinical features of this disease, per organ system, include:
Central nervous system
- Intellectual disability
- Dystonia
- Choreoathetosis
- Dysarthria
- Extrapyramidal symptoms
- Sensorineural deafness
- White matter lesions
- Decreased signal intensities in basal ganglia
- Other rarer manifestations:
- Psychosis
- Hallucinations
Head and neck
- Dysmorphic facial features (some patients), including:
- Triangular face
- Prominent ears
- Prominent nasal root
- Anodontia
Skin and hair
- Alopecia
- Loss of eyebrow hair
Endocrine
- Diabetes mellitus
- Hypogonadotropic or hypergonadotropic hypogonadism
- Failure of secondary sexual development
Genitourinary
- Small penis
- Small testes
- Hypospermatogenesis
- Atrophic seminiferous tubules
- Primary ovarian failure
- Hypoplastic uterus
- Streak ovaries
- Rudimentary fallopian tubes
- Vulvar hypoplasia
Laboratory features
- Decreased testosterone
- Decreased insulin-like growth factor 1
- Decreased estradiol
- Decreased thyroxine
- Increased thyroid-stimulating hormone
- Increased follicle-stimulating hormone
- Hyperlipidemia
Other(s)
- ECG Changes (nonspecific T-wave abnormalities)
The disease has a variable phenotype and a variable time of onset, with mental impairment commonly starting in early childhood and other symptoms starting in adolescence or early adulthood.