Pantothenate Kinase-Associated Neurodegeneration (PKAN) is a rare genetic disorder with an incidence of 1-2 per million.  It is an autosomal recessive condition, which means two copies of the disease-causing gene are needed to have symptoms.  In most cases, one copy of the disease-causing gene is inherited from each parent.  Since each parent has one working copy of the gene and one disease-causing gene, they have no symptoms, but in 25% of their offspring a child will have inherited a disease-causing gene from both parents and then have a PANK2 deficiency.

There are two types of PKAN, classic and atypical. Age of onset, severity of symptoms and progression are the differences between the two classifications. Classic disease starts in early childhood and progresses fairly rapidly.  Atypical PKAN usually starts in late childhood to early adulthood and progresses slowly.  There are common symptoms with both classic and atypical, including a specific brain MRI finding called an eye-of-the-tiger sign that can aid with diagnosis.