Recessive congenital myotonia resulting from maternal isodisomy of chromosome 7: a case report.
Autosomal dominant (Thomsen) and recessive (Becker) congenital myotonia are two different non dystrophic disorders, due to allelic mutations of the muscle chloride channel gene, located on chromosome 7q35. More than two thirds of the muscle chloride channel gene mutations occur independently in unique families and cause the recessive form of the disease. Becker disease is more common and severe than Thomsen disease. Here, we report on the clinical and molecular data of the first patient with maternal uniparental disomy for chromosome 7 and recessive congenital myotonia. The proband is a 15-year-old male, homozygous for a missense mutation within muscle chloride channel gene, showing few characteristic signs of the Silver Russell Syndrome.
Bulli
Cristina
C
Department of Biopathology, Genetics Unit, Tor Vergata University of Rome, via Montpellier, 1, Rome 00133, Italy. cristina.bulli@gmail.com
Battistella
Pier Antonio
PA
Bordignon
Marta
M
Bramanti
Placido
P
Novelli
Giuseppe
G
Sangiuolo
Federica
F