Hereditary tyrosinemia type 1, also called hepatorenal tyrosinemia, is a genetic disorder that affects the breakdown of an amino acid called tyrosine. It is associated with the development of severe liver disease in infants and also linked to the development of kidney disease and nerve problems in children. The disease is inherited in an autosomal recessive fashion which means that in order to have the disease, a child must receive two defective genes, one from each parent. In families where both parents are carriers of the gene for the disease, there is a one in four risk that a child will have tyrosinemia.