Heptadecanoyl-L-carnitine is a long-chain acylcarnitine composed of heptadecanoic acid and L-carnitine . Levels of heptadecanoyl-L-carnitine are increased in dried blood spots from neonates with propionic or methylmalonic acidemias, inborn errors of metabolism characterized by a deficiency in the activity of propionyl-CoA carboxylase or L-methylmalonyl-CoA mutase or its cofactor 5-deoxyadenosylcobalamin, respectively.1
1.Malvagia, S., Haynes, C.A., Grisotto, L., et al.Heptadecanoylcarnitine (C17) a novel candidate biomarker for propionic and methylmalonic acidemias during expanded newborn screeningClin. Chim. Acta450342-348(2015)