Hartnup disease (MONDO_0009324) is a rare metabolic disorder belonging to the neutral aminoacidurias and characterized by abnormal renal and gastrointestinal transport of neutral amino acids (tryptophan, alanine, asparagine, glutamine, histidine, isoleucine, leucine, phenylalanine, serine, threonine, tyrosine and valine). Also known as: Hartnup disorder, aminoaciduria, Hartnup type, deficiency of tryptophan oxygenase, neutral 1 amino acid transport defect, neutral amino acid transport defect.