Cerebral Creatine Deficiency Syndrome 2 (GAMT)
Cerebral creatine deficiency syndrome 2 is an autosomal recessive disorder caused by pathogenic variants in the gene GAMT. Although it has been identified in multiple populations, it has a higher prevalence among individuals of Portuguese descent. Onset of the first clinical manifestations ranges from early infancy (age 3-6 months) to age three years. Affected individuals generally have severe intellectual disability and speech delay. Other symptoms including recurrent seizures, autistic behaviors, tremor or facial tics, and weak muscle tone. Life expectancy is limited, particularly in those who have multiple disabilities and severe seizures. To date, no genotype phenotype correlation has been established.
For information about carrier frequency and residual risk, please see the residual risk table.