Clinical and genetic characterization of three Iranian patients carrying the CLCN1 p.Pro452Leu variant.
Fatemeh Sadat Haghighi, Seyed Mehdi Kalantar, Nasrin Ghasemi et al.
✦ AI-curated · Sources linked
Case in brief
Three Iranian families were evaluated for clinical and electrical myotonia, characterized by delayed skeletal muscle relaxation after contraction. Whole-exome sequencing in the index patients identified the CLCN1 missense variant NM_000083.3(CLCN1)0.1355 C > T (p.Pro452Leu); Sanger sequencing and family co-segregation analysis were also performed. The clinical, neurological, electrophysiological, and genetic findings supported recessive myotonia congenita. The abstract does not report treatment or clinical resolution.
What made this case unusual
The report describes the CLCN1 p.Pro452Leu variant in three Iranian families whose combined clinical and genetic findings were consistent with recessive myotonia congenita.
Diagnostic / clinical pearl
In suspected myotonia congenita, integrating clinical and neurological assessment with electrophysiological findings and genetic testing can support diagnosis and inheritance classification.
Why it matters
The authors report that these findings expand the clinical and genetic spectrum of myotonia congenita.