Removal of a salivary gland does not produce a dry mouth, called xerostomia. However, radiation therapy to the mouth can cause the unpleasant symptoms associated with reduced salivary flow. Your doctor can prescribe medication or other conservative treatments that may reduce the dryness in these instances.
Harlequin Ichthyosis Causes. The harlequin ichthyosis is known to be genetic in nature. The ABC 12 gene, which directs the protein production that is necessary to have a normal skin growth, is being mutated which leads to this severe skin disorder. It is a gene that is responsible for the transportation of lipid.
Histidinemia is caused by mutations in the HAL gene, which provides instructions for making an enzyme called histidase. Histidase breaks down histidine to a molecule called urocanic acid. Histidase is active (expressed) primarily in the liver and the skin. HAL gene mutations lead to the production of a histidase enzyme that cannot break down histidine, which results in elevated levels of histidine in the blood and urine.