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. 2017 Feb 23:4:2329048X17691396.
doi: 10.1177/2329048X17691396. eCollection 2017 Jan-Dec.

Two Novel KCNQ2 Mutations in 2 Families With Benign Familial Neonatal Convulsions

Ghalia Al Yazidi  1   2 , Michael I Shevell  1   2 , Myriam Srour  1   2
Affiliations

Two Novel KCNQ2 Mutations in 2 Families With Benign Familial Neonatal Convulsions

Ghalia Al Yazidi et al. Child Neurol Open. .

Abstract

Benign familial neonatal convulsion is a rare autosomal dominant inherited epilepsy syndrome characterized by unprovoked seizures in the first few days of life, normal psychomotor development, and a positive intergenerational family history of neonatal seizures. Over 90% of the affected individuals have inherited causal mutations in KCNQ2, which encodes for the potassium voltage-gated channel subfamily Q, member 2. Mutations in KCNQ2 are also associated with a severe neonatal encephalopathy phenotype associated with poor seizure control and neurodevelopmental deficits. The authors report the clinical presentations, response to medication, and intrafamilial phenotypic variability in 2 families with benign familial neonatal convulsions, carrying previously unreported heterozygous missense mutations, c.1066C>G (p.Leu356Val) and c.1721G<A (p.Gly574Asp), in KCNQ2. The cases reported herein suggest that inherited missense mutations in KCNQ2 can be associated with an intermediate phenotype and illustrate the challenges associated with prognosis and counselling for individuals with inherited missense mutations in KCNQ2.

Keywords: BFNC; KCNQ2; benign familial neonatal convulsions.

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Conflict of interest statement

Declaration of Conflicting Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
Pedigrees of probands A (A) and B (B) illustrating the affected family members with benign familial neonatal convulsion (BFNC) and segregation of the mutations.
See this image and copyright information in PMC

References

    1. Ronen GM, Rosales TO, Connolly M, Anderson VE, Leppert M. Seizure characteristics in chromosome 20 benign familial neonatal convulsions. Neurology. 1993;43(7):1355–1360. - PubMed
    1. Wakai S, Kamasaki H, Itoh N, et al. Classification of familial neonatal convulsions. Lancet. 1994;344(8933):1376. - PubMed
    1. Weckhuysen S, Mandelstam S, Suls A, et al. KCNQ2 encephalopathy: emerging phenotype of a neonatal epileptic encephalopathy. Ann Neurol. 2012;71(1):15–25. - PubMed
    1. Biervert C, Schroeder BC, Kubisch C, et al. A potassium channel mutation in neonatal human epilepsy. Science. 1998;279(5349):403–406. - PubMed
    1. Singh NA, Charlier C, Stauffer D, et al. A novel potassium channel gene, KCNQ2, is mutated in an inherited epilepsy of newborns. Nat Genet. 1998;18(1):25–29. - PubMed

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