<unk>  is inherited in an X-linked dominant fashion and is associated with a mutation of the NSDHL gene. This gene encodes for the enzyme 3beta-hydroxy sterol dehydrogenase which catalyzes a step in the cholesterol biosynthetic pathway. Locations of this enzyme include the membranes of the endoplasmic reticulum and on the surface of intracellular lipid storage droplets. A shortage of the enzyme may allow potentially toxic byproducts of cholesterol production to accumulate in the body's tissues. Mutations of the gene have been reported in all three types: missense, nonsense, and stop mutations, all resulting in loss of function of NSDHL. The type of mutation is not believed to be the underlining reason for clinical variations in the extent of involvement but rather the differences in the pattern of X inactivation. Although researchers suspect that low levels of cholesterol and/or an accumulation of other substances are responsible for disrupting the growth and development of many body parts, the precise rationale for the laterality of the<unk>  has yet to be determined.
CHILD syndrome
MOMO syndrome
Cystic fibrosis
Combined pulmonary fibrosis and emphysema
Mineral dust airway disease
complications of Idiopathic pulmonary fibrosis
Alpha-1 antitrypsin deficiency
SUNCT syndrome