Families

LBSL is a very rare condition of the white matter of the brain and spinal cord, caused by mutations in the DARS2gene. The white matter contains the "wiring" of the nervous system. In LBSL the signals that control movement and that carry feeling from the legs are affected. Most people first notice problems in childhood or the teenage years: clumsiness, unsteady walking and stiff legs, which very slowly get worse over many years. There is also a rare, much more severe form that starts before or shortly after birth.

The condition is inherited in an autosomal recessive way: both parents carry one changed copy of the gene without having the disease themselves, and each future pregnancy has a 25% chance of a child with the condition.