Spanish researchers report clinical and biological data from two unrelated consanguineous families in which a new gene for early-onset myopathy has been identified:
- the first (comprising two affected cousins) belonged to the Bedouin community in Israel and the other was of Egyptian origin (a single affected individual),
- the clinical picture consisted of proximal muscle weakness appearing in childhood, ptosis, low body weight, and significantly elevated muscle enzymes (up to ten times the normal value),
- a whole exome study revealed distinct homozygous variants (in both families) in the CACNB1 gene, the pathogenicity of which was confirmed by functional studies.
This gene is involved in excitation-contraction coupling in connection with the dihydropyridine receptor, for which it encodes a subunit.
