<P> Signs and symptoms of this disorder include low levels of ketones (products of fat breakdown that are used for energy) and low blood sugar (hypoglycemia). Together these signs are called hypoketotic hypoglycemia . People with this disorder typically also have an enlarged liver (hepatomegaly), muscle weakness, and elevated levels of carnitine in the blood . </P> <P> Mutations in the CPT1A gene cause carnitine palmitoyltransferase I deficiency by producing a defective version of an enzyme called carnitine palmitoyltransferase I. Without this enzyme, long - chain fatty acids from food and fats stored in the body cannot be transported into mitochondria to be broken down and processed . As a result, excessive levels of long - chain fatty acids may more rapidly build up in tissues, damaging the liver, heart and / or brain . </P> <P> This condition has an autosomal recessive inheritance pattern, which means the defective gene is located on an autosome, and two copies of the gene - one from each parent - must be inherited to be affected by the disorder . The parents of a child with an autosomal recessive disorder are carriers of one copy of the defective gene, but are usually not affected by the disorder . </P> <P> The prevalence of mutations associated with this condition reach 68% to 81% in certain arctic coastal populations, suggesting that the condition had some adaptive value in those habitats at some time . </P>

Carnitine palmitoyltransferase i (cpt i) deficiency