Histidinemia
Histidinemia is an inherited metabolic condition characterized by elevated levels of the amino acid histidine in blood, urine, and cerebrospinal fluid. In most cases, people with this condition have no health problems and may not even know that they are affected. Individuals with histidinemia who also experience a medical complication during or shortly after birth (such as a temporary lack of oxygen), may be at an increased risk of developing intellectual disability, behavioral problems, or learning disabilities.
Histidinemia is caused by changes (mutations) in the HAL gene. This gene provides instructions for making an enzyme called histidase, which breaks down histidine into a molecule called urocanic acid. If histidase doesn't do its job properly, histidine levels become elevated. Histidinemia is inherited in an autosomal recessive pattern. Because there are no symptoms associated with this condition, treatment is not necessary.
Histidinemia is caused by changes (mutations) in the HAL gene. This gene provides instructions for making an enzyme called histidase, which breaks down histidine into a molecule called urocanic acid. If histidase doesn't do its job properly, histidine levels become elevated. Histidinemia is inherited in an autosomal recessive pattern. Because there are no symptoms associated with this condition, treatment is not necessary.