Angelman syndrome
Definition:
Angelman syndrome is a genetic disorder that causes developmental disabilities and neurological problems, such as difficulty speaking, balancing and walking and, in some cases, seizures. Frequent smiles and outbursts of laughter are common for people with Angelman syndrome, and many have happy, excitable personalities.
Angelman syndrome usually isn't detected until parents begin to notice developmental delays when a baby is about 6 to 12 months old. Seizures often begin when a child is between 2 and 3 years old.
People with Angelman syndrome tend to live a normal life span, but they may become less excitable with age. Other signs and symptoms remain. Treatment for Angelman syndrome focuses on managing the child's medical and developmental problems.
Symptoms:
Characteristic Angelman syndrome signs and symptoms include:
Most babies with Angelman syndrome don't show signs or symptoms of the disorder when they're born. The first signs of Angelman syndrome are usually developmental delays, such as lack of crawling or babbling, between 6 and 12 months.
If your child seems to have developmental delays, or if your child has other signs or symptoms of Angelman syndrome, make an appointment to talk with your child's doctor.
Causes:
Angelman syndrome is a genetic disorder. It's most often caused by problems with a gene located on chromosome 15 called the ubiquitin-protein ligase E3A (UBE3A) gene.
Genes are segments of DNA that provide the blueprints for all of your characteristics. You receive your genes, which occur in pairs, from your parents. One copy comes from your mother (maternal copy), and the other copy comes from your father (paternal copy).
A missing or defective gene
Both genes in a pair usually are active. This means that your cells use information from both the maternal copy and the paternal copy of each gene pair. But in a small number of genes, only one copy of a gene pair is active. The activity of each gene copy depends on whether it was passed from your mother or from your father. This parent-specific gene activity is called imprinting. In these genes, when the copy that's usually active is missing or defective, it causes problems in the functions and characteristics controlled by that gene.
Normally, only the maternal copy of the UBE3A gene is active in the brain, caused by what's known as genomic imprinting. Most cases of Angelman syndrome occur when part of the maternal chromosome 15, which contains this gene, is missing or damaged. In a small number of cases, Angelman syndrome is caused when two paternal copies of the gene are inherited, instead of one paternal and one maternal copy (paternal uniparental disomy).
Complications:
Complications associated with Angelman syndrome include:
Treatments and drugs:
Because there isn't a way to repair chromosome defects, there's no cure for Angelman syndrome. Treatment focuses on managing the medical and developmental problems that the chromosome defects cause.
A team of health care professionals will likely work with you to manage your child's condition. Depending on your child's signs and symptoms, treatment for Angelman syndrome may involve the following:
Definition:
Angelman syndrome is a genetic disorder that causes developmental disabilities and neurological problems, such as difficulty speaking, balancing and walking and, in some cases, seizures. Frequent smiles and outbursts of laughter are common for people with Angelman syndrome, and many have happy, excitable personalities.
Angelman syndrome usually isn't detected until parents begin to notice developmental delays when a baby is about 6 to 12 months old. Seizures often begin when a child is between 2 and 3 years old.
People with Angelman syndrome tend to live a normal life span, but they may become less excitable with age. Other signs and symptoms remain. Treatment for Angelman syndrome focuses on managing the child's medical and developmental problems.
Symptoms:
Characteristic Angelman syndrome signs and symptoms include:
- Developmental delays, such as lack of crawling or babbling at 6 to 12 months, and intellectual disability
- Lack of or minimal speech
- Inability to walk, move or balance well (ataxia)
- Trembling movement of arms and legs
- Frequent smiling and laughter
- Happy, excitable personality
- Seizures, usually beginning between 2 and 3 years of age
- Stiff or jerky movements
- Small head size, with flatness in the back of the head (microbrachycephaly)
- Crossing of the eyes (strabismus)
- Tongue thrusting
- Walking with arms up in the air
- Light pigmentation in hair, skin and eyes (hypopigmentation)
Most babies with Angelman syndrome don't show signs or symptoms of the disorder when they're born. The first signs of Angelman syndrome are usually developmental delays, such as lack of crawling or babbling, between 6 and 12 months.
If your child seems to have developmental delays, or if your child has other signs or symptoms of Angelman syndrome, make an appointment to talk with your child's doctor.
Causes:
Angelman syndrome is a genetic disorder. It's most often caused by problems with a gene located on chromosome 15 called the ubiquitin-protein ligase E3A (UBE3A) gene.
Genes are segments of DNA that provide the blueprints for all of your characteristics. You receive your genes, which occur in pairs, from your parents. One copy comes from your mother (maternal copy), and the other copy comes from your father (paternal copy).
A missing or defective gene
Both genes in a pair usually are active. This means that your cells use information from both the maternal copy and the paternal copy of each gene pair. But in a small number of genes, only one copy of a gene pair is active. The activity of each gene copy depends on whether it was passed from your mother or from your father. This parent-specific gene activity is called imprinting. In these genes, when the copy that's usually active is missing or defective, it causes problems in the functions and characteristics controlled by that gene.
Normally, only the maternal copy of the UBE3A gene is active in the brain, caused by what's known as genomic imprinting. Most cases of Angelman syndrome occur when part of the maternal chromosome 15, which contains this gene, is missing or damaged. In a small number of cases, Angelman syndrome is caused when two paternal copies of the gene are inherited, instead of one paternal and one maternal copy (paternal uniparental disomy).
Complications:
Complications associated with Angelman syndrome include:
- Feeding difficulties. Some infants with Angelman
syndrome have problems feeding during the first few months of life
because of an inability to coordinate sucking and swallowing. If your
child has difficulty feeding, your pediatrician may recommend a
high-calorie formula to help your baby gain weight.
- Hyperactivity. Many young children with Angelman
syndrome have increased motor activity. They may move quickly from one
activity to another, often keeping their hands or a toy in their mouths.
Their attention span may be very short. Hyperactivity often decreases
with age in children with Angelman syndrome, and medication usually
isn't necessary.
- Sleep disorders. It's common for people with
Angelman syndrome to have abnormal sleep-wake patterns and to need less
sleep than normal. In some cases, sleep difficulties may improve with
age. Medication and behavior therapy may help control sleep disorders.
- Curving of the spine (scoliosis). Some people with Angelman syndrome develop this abnormal side-to-side spinal curvature over time.
- Obesity. Older children with Angelman syndrome tend to have large appetites, which lead to obesity.
Treatments and drugs:
Because there isn't a way to repair chromosome defects, there's no cure for Angelman syndrome. Treatment focuses on managing the medical and developmental problems that the chromosome defects cause.
A team of health care professionals will likely work with you to manage your child's condition. Depending on your child's signs and symptoms, treatment for Angelman syndrome may involve the following:
- Anti-seizure medication. Medication may be necessary to control seizures caused by Angelman syndrome.
- Physical therapy. Children with Angelman syndrome
may learn to walk better and overcome other movement problems with the
help of physical therapy.
- Communication therapy. Although people with
Angelman syndrome usually don't develop verbal language beyond simple
sentences, communication therapy can be helpful. Nonverbal language
skills may be developed through sign language and picture communication.
- Behavior therapy. Behavior therapy can help children with Angelman syndrome overcome hyperactivity and a short attention span, which can aid in developmental progress. Although the level of development people with Angelman syndrome can achieve varies widely, many are outgoing and are able to build relationships with friends and family.
Facebook
0 komentar:
Posting Komentar