Refsum like disorder in a Norwegian cosanguineous family

T. Fiskerstrand, MD, PhD, P. Knappskog, PhD, J. Majewski, PhD, R. J. Wanders, PhD, H. Boman, MD, PhD and L. A. Bindoff, MD, PhD .  A novel Refsum-like disorder that maps to chromosome 20.  NEUROLOGY 2009;72:20-27

This slowly progressive disorder starts in childhood with signs of peripheral neuropathy (pes cavus, tendoachilles contracture). Hearing loss and cataract become evident in the third decade. Subsequently, patients develop a disorder of gait due to the combination of ataxia and spasticity, and a pigment retinopathy. While the clinical picture is reminiscent of Refsum disease, affected individuals have normal phytanic and pristanic acid levels in plasma, as well as normal enzymatic activity for -oxidation. We mapped the disease to a 15.96 Mb region on chromosome 20 (20p11.21-q12), containing approximately 200 genes (maximum lod score = 6.3).