Carnitine palmitoyltransferase (CPT) II is one of a pivotal enzyme in mitochondrial fatty acid oxidation, which is essential for energy production during simultaneous glucose sparing and a requirement for major energy supply, such as prolonged fasting or exercise. When infants require more energy than provided by the glycolytic system, they rely on the mitochondrial fatty acid oxidation pathway. Mutations of the
CPT2 gene have been reported to cause sudden unexpected death in infancy (SUDI). A thermolabile phenotype of a
CPT2 polymorphism (F352C) has been recently reported to reduce CPT II enzyme activity. The F352C variant results in energy crisis at high temperature and is suspected as a risk factor for acute encephalopathy. However, a relationship between
CPT2 gene polymorphism and SUDI has not been described.
Methods
Single nucleotide polymorphisms of the CPT2 gene were investigated among 54 SUDI cases and 200 healthy volunteers.
Results
The frequency of the C allele was significantly higher in the SUDI group than in the control group [25.0% vs 16.0%, odds ratio (OR) = 1.75, 95% confidence interval (CI) = 1.05–2.92, p = 0.030). The frequency of the F352C homozygote was significantly higher in the SUDI group than in control group (11.1% vs 3.5%, OR = 3.45, 95% CI = 1.11–10.73, p = 0.036).
Conclusion
The F352C CPT2 variant might be a genetic risk factor for SUDI.
