Niemann-Pick disease is an inherited condition involving lipid
metabolism (the breakdown and use of fats and cholesterol in the
body) in which harmful amounts of lipids accumulate in the
spleen, liver, lungs, bone marrow, and brain. There are three
variants of Niemann-Pick disease based on the genetic cause and
the symptoms exhibited by the patient. All variants are
inherited in an autosomal recessive pattern. Mutations in the
NPC1, NPC2, and SMPD1 genes cause Niemann-Pick disease. This
condition is inherited in an autosomal recessive pattern, which
means two copies of the gene must be altered for a person to be
affected by the disorder. Most often, the parents of a child
with an autosomal recessive disorder are not affected but are
carriers of one copy of the altered gene. If both parents are
carriers, there is a one in four, or 25%, chance with each
pregnancy for an affected child. Genetic counseling and genetic
testing is recommended for families who may be carriers of
Niemann-Pick. Type C is characterized