phenylketonuria (pku) a human disease characterized by mental retardation results from the
Phenylketonuria Phenylketonuria is a genetic disorder inherited from a person's parents.[1] It is due to mutations in the PAH gene, which results in low levels of the enzyme phenylalanine hydroxylase.[1] This results in the buildup of dietary phenylalanine to potentially toxic levels.[1] It is autosomal recessive, meaning that both copies of the gene must be mutated for the condition to develop.[1] There are two main types, classic PKU and variant PKU, depending on if any enzyme function remains.[1] Those with one copy of a mutated gene typically do not have symptoms.[1] Many countries have newborn screening programs for the disease.[3]
Kuru (disease) The term kuru derives from the Fore word kuria or guria ("to shake"),[1] due to the body tremors that are a classic symptom of the disease and kÃºru itself means "trembling".[2] It is also known as the "laughing sickness" due to the pathologic bursts of laughter which are a symptom of the disease. It is now widely accepted that kuru was transmitted among members of the Fore tribe of Papua New Guinea via funerary cannibalism. Deceased family members were traditionally cooked and eaten, which was thought to help free the spirit of the dead.[3] Women and children usually consumed the brain, the organ in which infectious prions were most concentrated, thus allowing for transmission of kuru. The disease was therefore more prevalent among women and children.