Untreated PKU can lead to:
Irreversible brain damage and marked intellectual disability beginning within the first few months of life
. Neurological problems such as seizures and tremors. Behavioral, emotional and social problems in older children and adults.
What are the causes and effects of phenylketonuria?
The disease is caused due to the defective gene of phenylalanine hydroxylase involved in the digestion of the amino acid phenylalanine. When the phenylalanine is not broke down, it starts accumulating in the body. Effects:
Intellectual problems
.
How does phenylketonuria affect development?
The developing baby in the uterus can be exposed to very high levels of phenylalanine. This can cause
low birth weight, slow growth, small head, behavior problems, and heart disorders
.
How is the family of a person with PKU affected?
As PKU is inherited in an autosomal recessive fashion,
all children of a mother with PKU will inherit 1 affected gene
.
How does phenylketonuria cause albinism?
Phenylketonuria (PKU) is an autosomal recessive metabolic genetic disorder characterized by
a mutation in the gene for the hepatic enzyme phenylalanine hydroxylase (PAH)
. The disease may present clinically with seizures, albinism (excessively fair hair and skin), and a “musty odor” to the baby’s sweat and urine.
What mutations cause PKU?
Causes.
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.
What is PKU diet?
The diet for PKU consists of
a phenylalanine-free medical formula and carefully measured amounts of fruits, vegetables, bread, pasta, and cereals
. Many people who follow a low phenylalanine (phe) food pattern eat special low protein breads and pastas.
Can you develop phenylketonuria later in life?
In rare cases, the first sign of PKU develops in the late adulthood
resembling common manifestations of neurological diseases such as progressive dementia, spastic paraplegia, ataxia, tremor, and behavioral problems.
What chromosome affects PKU?
Classical PKU is an autosomal recessive disorder, caused by mutations in both alleles of the gene for phenylalanine hydroxylase (PAH), found on
chromosome 12
.
As children and adolescents, patients with PKU may have learning difficulties, school problems, decreased motivation,
less social competence
, irritability, hyperactivity, mood disorders, and poor self esteem.
Can a person with PKU have children?
Girls or women with PKU can have healthy children as long as they are aware of and maintain strict adherence to their low phenylalanine diet throughout their pregnancy
.
Can a baby with PKU breastfeed?
Can I breastfeed my baby if I have PKU?
Yes you can breastfeed
! Breastfeeding is possible for women who have normal babies and who have phe levels in the safe range.
How does PKU affect a child?
Children with PKU can’t process an amino acid called phenylalanine. Phenylalanine is in many common foods. But it can build up in the bloodstream of children with PKU. This
can cause growth, mood, behavior, and thinking problems, as well as other problems ranging from mild to severe
.
What is the life expectancy of a person with phenylketonuria?
PKU does not shorten life expectancy, with or without treatment
. Newborn screening for PKU is required in all 50 states. PKU is usually identified by newborn screening. A child’s outlook is very good if she strictly follows the diet.
What is the effect of the mutation on the cell tissue phenylketonuria?
Mutations in the PAH gene can cause phenylketonuria (PKU), a disorder that can change cells in the brain. The faulty protein allows dangerously high levels of phenylalanine to accumulate in the brain,
poisoning the cells
. If a person with PKU consumes too much phenylalanine, the build-up can cause mental retardation.
Why do people with phenylketonuria have light skin?
Children with PKU have
lower levels of melanin
, the substance that gives color to hair and skin. That’s because when phenylalanine is broken down, one of its products is used to make melanin. As a result, children with PKU often will have pale skin, blond hair and blue eyes.
When does phenylketonuria develop?
Babies with PKU usually seem healthy at birth. Signs of PKU begin to appear
around six months of age
.
What can people with PKU not have?
People with PKU must avoid
foods that are high in protein like meat, fish, poultry, dairy, soy, legumes (dried beans) or nuts
. Some fruits and vegetables are higher in protein than others. PHE is in almost everything except sugar, salt, oil, and water.
How can PKU be prevented?
Because PKU is a genetic condition,
it can’t be prevented or avoided
. Genetic testing is the only way to determine if people carry the defective gene. Some people may carry the gene but not have PKU. These people are called carriers.
