Definition of Ferritin

Ferritin: The major iron storage protein. The blood level of ferritin serves as an indicator of the amount of iron stored in the body.

Ferritin has the shape of a hollow sphere that permits the entry of a variable amount of iron for storage (as ferric hydroxide phosphate complexes). Liver and spleen ferritin consists of 24 subunits of 2 kinds, the heavy and the light subunit. The genes that encode the light and heavy chains are on different chromosomes. The light chain genes are in chromosome region 19q13.3-q13.4 while those for the heavy chain are in chromosome region 11q12-q13.

Mutations in the ferritin light chain are responsible for a disease called the hyperferritinemia-cataract syndrome characterized by cataracts (opacities in the lens of the eye) and high levels of ferritin in the blood.