What is Glut1 Deficiency?
Glut1 Deficiency, G1D, Glut1 DS, or De Vivo Disease
Glucose Transporter Type 1 Deficiency Syndrome is a genetic disorder that impairs brain metabolism. Glucose isn’t transported properly into the brain, leaving it starving for the energy it needs to grow and function.
Glut1 Deficiency is caused by a mutation in the SLC2A1 gene, which regulates the glucose transporter protein type 1 (Glut1). Glut1 is the principal transporter of glucose, the primary source of energy, across the blood-brain barrier. More than 100 different types of mutations and deletions of this gene have been found to date in Glut1 Deficiency patients.
The impaired glucose transport associated with Glut1 Deficiency causes an array of symptoms which may vary considerably from one patient to another and can change and evolve over time. Some of the most common signs and symptoms may include seizures, movement disorders, speech and language disorders, and developmental delays. Not all patients experience all symptoms, especially in the milder cases. There are currently a few hundred patients diagnosed worldwide, but experts believe there are thousands more yet to be discovered.
There is currently no cure for Glut1 Deficiency. The recommended standard treatment is a ketogenic diet, which helps improve most symptoms for most patients, even in adulthood. A ketogenic diet gives the brain an alternate source of energy and helps optimize brain growth and development.
Could it be Glut1 Deficiency?
The hallmark symptoms of classical Glut1 Deficiency are seizures (approximately 90% of patients), a complex movement disorder, developmental delay and intellectual disability, and speech/language impairments. There is a great deal of variance across a wide spectrum in both the combination and severity of symptoms from one patient to another, and symptoms may evolve over time.
Suggestive symptoms seen in many Glut1 Deficiency patients:
(please see our Key Terms resource for a more complete list with definitions)
Other conditions sometimes diagnosed in patients with Glut1 Deficiency:
Key Terms in Glut1 Deficiency
Brochures
Professional Guide
Diagnostic Protocol
Additional Resources
Research Updates
Glut1 Deficiency is caused by a mutation in the SLC2A1 gene, which regulates the glucose transporter protein type 1 (Glut1). Glut1 is the principal transporter of glucose, the primary source of energy, across the blood-brain barrier. More than 100 different types of mutations and deletions of this gene have been found to date in Glut1 Deficiency patients.
The impaired glucose transport associated with Glut1 Deficiency causes an array of symptoms which may vary considerably from one patient to another and can change and evolve over time. Some of the most common signs and symptoms may include seizures, movement disorders, speech and language disorders, and developmental delays. Not all patients experience all symptoms, especially in the milder cases. There are currently a few hundred patients diagnosed worldwide, but experts believe there are thousands more yet to be discovered.
There is currently no cure for Glut1 Deficiency. The recommended standard treatment is a ketogenic diet, which helps improve most symptoms for most patients, even in adulthood. A ketogenic diet gives the brain an alternate source of energy and helps optimize brain growth and development.
Could it be Glut1 Deficiency?
The hallmark symptoms of classical Glut1 Deficiency are seizures (approximately 90% of patients), a complex movement disorder, developmental delay and intellectual disability, and speech/language impairments. There is a great deal of variance across a wide spectrum in both the combination and severity of symptoms from one patient to another, and symptoms may evolve over time.
Suggestive symptoms seen in many Glut1 Deficiency patients:
(please see our Key Terms resource for a more complete list with definitions)
- paroxysmal exercise-induced dystonia/dyskinesia (PED) (movement episodes triggered by exercise)
- early onset absence seizures before the age of 3
- treatment resistant seizures/epilepsy at any age
- movement and balance issues (ataxia, dystonia, chorea, tremor, gait abnormalities, and others)
- fluctuation of symptoms with hunger, fatigue, heat, illness, anxiety, stress, excitement
- symptoms worse just after waking in the morning
- symptom improvement after eating
- opsoclonus-like darting and dancing eye/head movements in first two years of life (aberrant gaze saccades)
- paroxysmal neurological symptoms (transient or episodic - not there all the time)
(seizures, movement disturbances, hemiplegia episodes, headaches, energy levels, confusion, mood) - speech difficulties
- Dystonia 9 and Dystonia 18 are associated with the SLC2A1 gene and are considered part of the phenotypic spectrum.
Other conditions sometimes diagnosed in patients with Glut1 Deficiency:
- epilepsy
- cerebral palsy
- ataxia
- dystonia
- autism
- hemolytic anemia
- ADHD
- alternating hemiplegia of childhood
Key Terms in Glut1 Deficiency
Brochures
Professional Guide
Diagnostic Protocol
Additional Resources
Research Updates
