What is the life expectancy of someone with phenylketonuria?
With prompt diagnosis and treatment, people with phenylketonuria can avoid the most severe symptoms associated with this disorder and experience normal development. Their life expectancy will most likely be no different from someone without the disorder.
Is phenylketonuria a single gene disorder?
What is phenylketonuria (PKU)? Phenylketonuria is a rare metabolic disorder that affects the way the body breaks down protein. If not treated shortly after birth, PKU can be destructive to the nervous system, causing mental retardation. PKU is caused by a mutation in a gene on chromosome 12.
Are phenylketonurics bad for You?
Phenylalanine isn't a health concern for most people. However, for people who have the genetic disorder phenylketonuria (PKU) or certain other health conditions phenylalanine can be a serious health concern. Phenylalanine can cause intellectual disabilities, brain damage, seizures and other problems in people with PKU.
Is phenylketonuria caused by a dominant or reccesive allele?
Phenylketonuria is a human hereditary disease that is manifested early in infancy and which, if it remains untreated, can cause mental retardation. PKU is caused by a recessive autosomal allele with simple Mendelian inheritance.
What kind of mutation causes phenylketonuria?
Mutations in the PAH gene cause phenylketonuria. The PAH gene provides instructions for making an enzyme called phenylalanine hydroxylase . This enzyme converts the amino acid phenylalanine to other important compounds in the body.
Does phenylketonuria results from a recessive gene?
PKU is inherited in an autosomal recessive pattern. Recessive genetic disorders occur when an individual inherits an abnormal gene from each parent. If an individual receives one normal gene copy and one abnormal gene copy, they will be a carrier for the condition, but will not have symptoms.
Who is mostly affected by phenylketonuria?
In the United States, PKU is most common in people of European or Native American ancestry. It is much less common among people of African, Hispanic, or Asian ancestry.
What is the PAH gene?
The PAH gene provides instructions for making an enzyme called phenylalanine hydroxylase. This enzyme is responsible for the first step in processing phenylalanine, which is a building block of proteins (an amino acid) obtained through the diet. Phenylalanine is found in all proteins and in some artificial sweeteners.
Is PKU a single gene disorder?
Phenylketonuria (PKU) is a prominent example of a single-gene disease with an autosomal recessive inheritance pattern.
What are the causes of phenylketonuria?
Causes of phenylketonuria PKU is an inherited condition caused by a defect in the PAH gene. The PAH gene helps create phenylalanine hydroxylase, the enzyme responsible for breaking down phenylalanine. A dangerous buildup of phenylalanine can occur when someone eats high-protein foods, such as eggs and meat.
How does phenylketonuria affect the body?
In a child with PKU, phenylalanine cannot be converted to tyrosine because the phenylalanine hydroxylase enzyme does not work properly. This results in dangerously high levels of phenylalanine that build up in the blood and become toxic to the brain and nervous system.
How many babies are born PKU?
In the United States, about 1 in 10,000 to 15,000 babies is born with PKU each year.
What happens if someone with PKU eat protein?
Without the enzyme necessary to break down phenylalanine, a dangerous buildup can develop when a person with PKU eats foods that contain protein or eats aspartame, an artificial sweetener. This can eventually lead to serious health problems.
On which chromosome PAH gene is located?
chromosome 12The human PAH gene is located on the long arm of chromosome 12 (12q23. 2). It contains 13 exons and 12 introns and spans about 90 kbp encoding a monomer of 452 amino acids (1, 9–12).
How many mutations of PKU are there?
Abstract. Phenylketonuria (PKU) is heterogeneous. More than 400 different mutations in the phenylalanine hydroxylase (PAH) gene have been identified.
Is phenylketonuria autosomal or Sexlinked?
Answer and Explanation: PKU is an autosomal recessive trait.
What are autosomal recessive traits?
Autosomal recessive inheritance is a way a genetic trait or condition can be passed down from parent to child. A genetic condition can occur when the child inherits one copy of a mutated (changed) gene from each parent. The parents of a child with an autosomal recessive condition usually do not have the condition.
Is a recessive inherited disorder caused by the deletion of the amino acid phenylalanine?
Phenylketonuria (PKU; MIM 261600) is an autosomal recessive metabolic disorder caused by a deficiency of phenylalanine hydroxylase (PAH; EC 1.14.
When does phenylketonuria develop?
Babies who have PKU seem normal for the first few months of life. But without treatment, they begin to show signs and symptoms of the illness at about 6 months of age.
Overview
Symptoms
Causes
Risk Factors
Complications
Prevention
- Newborns with PKU initially don't have any symptoms. However, without treatment, babies usually develop signs of PKUwithin a few months. Signs and symptoms of untreated PKUcan be mild or severe and may include: 1. A musty odor in the breath, skin or urine, caused by too much phenylalanine in the body 2. Nervous system (neurological) problems that may include seizures …