NEET PG Medical – 2018 – Question – 39
Chromosome involved in myotonic dystrophy is
a) Chromosome 19
b) Chromosome 20
c) Chromosome 21
d) Chromosome 22
Show Answer
Correct Answer – A
Answer: A – Chromosome 19
Myotonic dystrophy is transmitted by mutation in an ‘unstable trinucleotide repeat sequence’ in gene 19q 133.
Features:
- An autosomal dominant disorder
- Most common adult muscular dystrophy
Characteristics feature: - Myopathy is distal (in contrast to other myopathies – mostly proximal).
- Muscle atrophy selectively involves type I fibres only
- Appears by 5 years, causes a slow relaxation of hand grip following a forced voluntary closure.
