What is the difference between fragile X and Down syndrome?
Fragile X syndrome arises from a single gene mutation that prevents the synthesis of a protein required for neural development (Fragile X mental retardation protein). The presence of all or a part of a third copy of chromosome 21 in cells causes Down syndrome.
What are three symptoms of fragile X syndrome?
Symptoms
- Intellectual disabilities, ranging from mild to severe.
- Attention deficit and hyperactivity, especially in young children.
- Anxiety and unstable mood.
- Autistic behaviors, such as hand-flapping and not making eye contact.
- Sensory integration problems, such as hypersensitivity to loud noises or bright lights.
What is the characteristics of fragile X syndrome?
These features include a long and narrow face , large ears, a prominent jaw and forehead, unusually flexible fingers, flat feet , and in males, enlarged testicles (macroorchidism) after puberty.
What does Fragile X syndrome do to the brain?
Fragile X syndrome is caused by a change in the genetic material that mostly affects brain cells. This change makes it hard for cells to produce a protein that is needed for normal brain function.
Is Down syndrome caused by the mother or father?
There is no definitive scientific research that indicates that Down syndrome is caused by environmental factors or the parents’ activities before or during pregnancy. The additional partial or full copy of the 21st chromosome which causes Down syndrome can originate from either the father or the mother.
Can 2 Down syndrome parents have a normal child?
Parents with one baby with regular trisomy 21 are usually told that the chance of having another baby with Down’s syndrome is 1 in 100. Very few families are known who have more than one child with Down’s syndrome, so the real chance is probably less than this.
Can a person with Fragile X syndrome have FXS?
People who have 55 to 200 repeats are said to have a “premutation” in the FMR1 gene. They do not have FXS but they might have, or may later develop, other fragile X-associated disorder s. In addition, people with a premutation can have children with a premutation or full mutation (FXS).
Which is the most common form of Fragile X syndrome?
Fragile X syndrome is an inherited intellectual disability caused by a mutation in the FMR1 gene. What is fragile X syndrome? Fragile X syndrome is the most common form of inherited intellectual disability in males and is also a significant cause of intellectual disability in females.
Are there any prenatal tests for Fragile X syndrome?
A prenatal test allows healthcare providers to detect the mutated gene in the developing fetus. This important information helps families and providers to prepare for Fragile X syndrome and to intervene as early as possible. Possible types of prenatal tests include: Amniocentesis.
How is fragile X syndrome related to FMR1?
In people with fragile X syndrome, however, the CGG segment is repeated more than 200 times. The abnormally expanded CGG segment inactivates (silences) the FMR1 gene, which prevents the gene from producing a protein called fragile X mental retardation protein.