Question: What is (are) Primary carnitine deficiency ?
Answer: Primary carnitine deficiency is a genetic condition that prevents the body from using certain fats for energy, particularly during periods without food (fasting). The nature and severity of signs and symptoms may vary, but they most often appear during infancy or early childhood and can include severe brain dysfunction (encephalopathy), cardiomyopathy, confusion, vomiting, muscle weakness, and hypoglycemia. Some individuals may only have fatigability in adulthood, or no symptoms at all. This condition is caused by mutations in the SLC22A5 gene and is inherited in an autosomal recessive manner. Treatment and prevention of symptoms typically includes oral L-carnitine supplementation.
Source: GARD

Question: What causes Primary carnitine deficiency ?
Answer: What causes primary carnitine deficiency? Mutations in the SLC22A5 gene cause primary carnitine deficiency. This gene provides instructions for making a protein called OCTN2 that transports carnitine into cells. Cells need carnitine to bring certain types of fats (fatty acids) into mitochondria, which are the energy-producing centers within cells. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues. Mutations in the SLC22A5 gene result in an absent or dysfunctional OCTN2 protein. As a result, there is a shortage (deficiency) of carnitine within cells. This deficiency, as well as potential build-up of fatty acids within the cells, causes the signs and symptoms of the condition.
Source: GARD

Question: Is Primary carnitine deficiency inherited ?
Answer: How is primary carnitine deficiency inherited? Primary carnitine deficiency is inherited in an autosomal recessive manner. Individuals have two copies of each gene, one of which is inherited from each parent. For an individual to have an autosomal recessive condition, he/she must have a mutation in both copies of the disease-causing gene. The parents of an affected individual, who each likely have one mutated copy, are referred to as carriers. Carriers typically do not have any signs or symptoms of the condition. When two carriers for an autosomal recessive condition have children together, each child has a 25% (1 in 4) risk to have the condition, a 50% (1 in 2) risk to be a carrier like each of the parents, and a 25% risk to not have the condition and not be a carrier.
Source: GARD