Carnitine Palmitoyltransferase II Deficiency (CPT2)
Carnitine palmitoyltransferase II deficiency is an autosomal recessive disorder caused by pathogenic variants in the gene CPT2. While it is diagnosed in individuals worldwide, it has a higher prevalence among individuals of Ashkenazi Jewish descent. There are three forms of carnitine palmitoyltransferase II deficiency: (a) the lethal neonatal form, (b) the severe infantile hepatocardiomuscular form, and (c) the myopathic form. Both the lethal neonatal form and severe infantile hepatocardiomuscular form are severe multisystemic diseases. Symptoms include liver failure with hypoketotic hypoglycemia, cardiomyopathy, cardiac arrhythmias, seizures, and early death. These symptoms are present shortly after birth or within the first year of life. The myopathic form presents between the first to sixth decade of life and includes symptoms of muscle pain and weakness during periods of prolonged exercise, cold exposure, or stress. Specific variants have been associated with the different forms of the disease, and therefore it may be possible to predict the phenotype in some patients.
For information about carrier frequency and residual risk, please see the residual risk table.