Hereditary tyrosinemia type 1 (HT1), the most severe inborn error of the tyrosine degradation pathway, is due to a deficiency in fumarylacetoacetate hydrolase (FAH). The worldwide frequency of HT1 is one per 100,000 births, but some regions have a significantly higher incidence (1:1,800). The FAH defect results in the accumulation of toxic metabolites, mainly in the liver. If left untreated, HT1 is usually fatal before the age of two. HT1 patients develop several chronic complications including cirrhosis with a high risk of hepatocellular carcinoma (HCC) and neuropsychological impairment. Treatment comprises an inhibitor of the pathway, Nitisinone, a strict dietary treatment or liver transplantation. Early treatment is important to avoid HCC. The book includes the latest developments on the molecular basis of HT1, its pathology, screening and diagnosis and management of the disease written by leading scientists, geneticists, hepatologists and clinicians in the field.
