18.03.16 FSHD

Question 1

Give an overview of FSHD, including its incidence.

Answer 1

Third most common muscular dystrophy (after DMD and DM)

Two forms: FSHD1, FSHD2 - phenotypically indistinguishable.

Prevalence = ~1 in 20,000, but may be more frequent
Approx. 95% penetrance by age of 20, but recent studies suggest this may be lower

Phenotype:
Asymmetrical progressive muscle weakness.
Normally presents with asymmetric weakness in facial muscles
Progresses to affect muscles in shoulder and upper arm, hip girdle and lower leg
Often show scapular winging = protrusion of the shoulder blades
Age of onset: Majority of cases become symptomatic by second or third decade of life