Fragile X syndrome

Question 1

Describe the genetic abnormality in Fragile X

Answer 1

trinucleotide CGG repeat disorder

Question 2

Features of Fragile X in males

Answer 2

learning difficulties
large low set ears, long thin face, high arched palate
macroorchidism
hypotonia
autism is more common
mitral valve prolapse

Question 3

Females with Fragile X typically don’t show symptoms. TRUE/FALSE?

Answer 3

FALSE
Features in females who have one fragile chromosome and one normal X chromosome can range from normal to mild

Question 4

Fragile X can be diagnosed antenatally. What tests can be completed to do this?

Answer 4

chorionic villus sampling or amniocentesis

Question 5

How is the trinucleotide repeat assessed in a sample?

Answer 5

restriction endonuclease digestion and Southern blot analysis