| Phenotype details |
Myopathy, Skeletal muscle hypertrophy, Global developmental delay, Delayed speech and language development, Abnormality of the neck, Myotonia with warm-up phenomenon; Climbing stairs difficult possible up stairs, down stairs much better, no muscle weakness, warm up phenomenon, jaw and tongue muscles also affected, low hairline, broad neck, below average learning and performance abilities, speech disorder, CK normal. |