Restless legs syndrome (RLS) is a neurologic sleep/wake disorder characterized by uncomfortable and unpleasant sensations in the legs that appear at rest, usually at night, inducing an irresistible desire to move the legs. The disorder results in nocturnal insomnia and chronic sleep deprivation (Bonati et al., 2003). Genetic Heterogeneity of Restless Legs Syndrome RLS1 has been mapped to chromosome 12q. Other susceptibility loci for RLS include RLS2 (608831) on chromosome 14q13-q31; RLS3 (610438) on chromosome 9p24-p22; RLS4 (610439) on chromosome 2q33; RLS5 (611242) on chromosome 20p13; RLS6 (611185) on chromosome 6p21; RLS7 (612853) on chromosome 2p14; and RLS8 (615197) on chromosome 5q31.

A rare genetic haematologic disease characterised by decreased or undetectable serum L-ferritin with otherwise normal laboratory parameters. Clinical signs and symptoms include generalised seizures, atypical restless leg syndrome, mild neuropsychologic impairment and progressive hair loss. Asymptomatic cases have also been reported.