U.S. flag

An official website of the United States government

GTR Home > Conditions/Phenotypes > Creatine transporter deficiency

Creatine transporter deficiency

Synonyms
CEREBRAL CREATINE DEFICIENCY SYNDROME 1; CREATINE TRANSPORTER DEFECT; Creatine deficiency, X-linked; Mental retardation , X-linked with seizures, short stature and midface hypoplasia; Mental retardation , X-linked, with creatine transport deficiency; SLC6A8-Related Creatine Transporter Deficiency; X-linked creatine deficiency syndrome; X-linked creatine transporter deficiency
Modes of inheritance
X-linked recessive inheritance (Orphanet)
Not genetically inherited (Orphanet)

Summary

Excerpted from the GeneReview: Creatine Deficiency Disorders
The creatine deficiency disorders (CDDs), inborn errors of creatine metabolism and transport, comprise three disorders: the creatine biosynthesis disorders guanidinoacetate methyltransferase (GAMT) deficiency and L-arginine:glycine amidinotransferase (AGAT) deficiency; and creatine transporter (CRTR) deficiency. Developmental delay and cognitive dysfunction or intellectual disability and speech-language disorder are common to all three CDDs. Onset of clinical manifestations of GAMT deficiency (reported in ~130 individuals) is between ages three months and two years; in addition to developmental delays, the majority of individuals have epilepsy and develop a behavior disorder (e.g., hyperactivity, autism, or self-injurious behavior), and about 30% have movement disorder. AGAT deficiency has been reported in 16 individuals; none have had epilepsy or movement disorders. Clinical findings of CRTR deficiency in affected males (reported in ~130 individuals) in addition to developmental delays include epilepsy (variable seizure types and may be intractable) and behavior disorders (e.g., attention deficit and/or hyperactivity, autistic features, impulsivity, social anxiety), hypotonia, and (less commonly) a movement disorder. Poor weight gain with constipation and prolonged QTc on EKG have been reported. While mild-to-moderate intellectual disability is commonly observed up to age four years, the majority of adult males with CRTR deficiency have been reported to have severe intellectual disability. Females heterozygous for CRTR deficiency are typically either asymptomatic or have mild intellectual disability, although a more severe phenotype resembling the male phenotype has been reported.
Full text of GeneReview (by section):
Summary
GeneReview Scope
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Saadet Mercimek-Andrews
Gajja S Salomons
view full author information

Available tests

91 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (91 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: CCDS1, CRT, CRT-1, CRT1, CRTR, CT1, CTR5, SLC6A8
    Summary: solute carrier family 6 member 8

Clinical features

Help
Imported from Human Phenotype Ontology (HPO)

Show allHide all

IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.