8: Fragile X Syndrome Flashcards Preview

Simmons NURP 503 Exam 3 > 8: Fragile X Syndrome > Flashcards

Flashcards in 8: Fragile X Syndrome Deck (11):

Name clinical presentations for fragile X (6).

1. Long and protruding ears
2. Long, thin face with prominent jaw
3. Epicanthal folds
4. High-arched palate
5. Increased head circumference
6. Large testes


Normal people have 6-50 FMR1 gene repeats. Carriers have _____. Significantly affected people have _____.

Up to 200.
More than 200.


High risk populations for fragile X (3).

1. Children with IDD of unknown etiology.
2. Children with family hx of IDD.
3. Persons diagnosed with autism spectrum disorder.


What medications can be used for behavior problems (3)?

1. Ritalin
2. Dexedrine
3. Clonidine


What causes the problems in fragile X?

Absence of FMR1 protein production.


Do males or females have milder symptoms of fragile X?

Females. Affects both sexes, but females have milder symptoms (likely d/t more than 1 X chromosome).


T/F Estimated 1:5,000 are born with fragile X.



What is the average age of diagnosis (2)?

1. Males: 36 months
2. Females: 42 months


The X gene has a unique, _____ expansion.

Trinucleotide. Everyone has FMR1, but when the repeat expansion increases in size, it causes silencing of the gene. This leads to a deficiency or lack of the FMR1 protein.


Where is the mutation in fragile X?

Fragile MR 1 (FMR) gene located at Xq27.3


Why might females have milder symptoms?

They have 2 X chromosomes.