Timothy syndrome 1 genotype without syndactyly and major extracardiac manifestations

Róbert Sepp, Lidia Hategan, Attila Bácsi, Judit Cseklye, László Környei, János Borbás, Márta Széll, T. Forster, István Nagy, Zoltán Hegedűs

Research output: Article

6 Citations (Scopus)

Abstract

Timothy syndrome 1 (TS1) is a rare genetic disorder characterized by multisystem abnormalities including QT prolongation, congenital heart defects, facial dysmorphism, episodic hypoglycemia, and neurological symptoms. A morphological hallmark of TS1 is syndactyly, present in all cases. TS1 is caused by the canonical p.Gly406Arg mutation in the alternatively spliced exon 8A in the CACNA1C gene, encoding for the main cardiac L-type calcium channel. A variant case of TS1 is reported. The proband had intermittent fetal bradycardia with heart rate of 72 bpm. On the first day of life bradycardia due to 2:1 atrioventricular (AV) block and marked QTc prolongation of 600 ms was noted. On medical therapy with propranolol and mexiletine 1:1 AV conduction returned with QTc prolongation of 470–580 ms. The patient lacked other extracardiac manifestations, most importantly syndactyly, neurological complications or autism. On genetic analysis, the canonical TS1 causing mutation, p.Gly406Arg in exon 8A of the CACNA1C gene was detected. The CACNA1C p.Gly406Arg variant was not present in the parents, but was detected in different DNA samples of the index patient. Our case highlight further phenotypic variability in TS. Most importantly, it underlines that the lack of syndactyly does not exclude the presence of a TS1 genotype.

Original languageEnglish
Pages (from-to)784-789
Number of pages6
JournalAmerican Journal of Medical Genetics, Part A
Volume173
Issue number3
DOIs
Publication statusPublished - márc. 1 2017

Fingerprint

Syndactyly
Genotype
Bradycardia
Exons
Mexiletine
L-Type Calcium Channels
Mutation
Inborn Genetic Diseases
Congenital Heart Defects
Atrioventricular Block
Autistic Disorder
Hypoglycemia
Propranolol
Genes
Timothy syndrome
Heart Rate
Parents
DNA

ASJC Scopus subject areas

  • Genetics
  • Genetics(clinical)

Cite this

Sepp, R., Hategan, L., Bácsi, A., Cseklye, J., Környei, L., Borbás, J., ... Hegedűs, Z. (2017). Timothy syndrome 1 genotype without syndactyly and major extracardiac manifestations. American Journal of Medical Genetics, Part A, 173(3), 784-789. https://doi.org/10.1002/ajmg.a.38084

Timothy syndrome 1 genotype without syndactyly and major extracardiac manifestations. / Sepp, Róbert; Hategan, Lidia; Bácsi, Attila; Cseklye, Judit; Környei, László; Borbás, János; Széll, Márta; Forster, T.; Nagy, István; Hegedűs, Zoltán.

In: American Journal of Medical Genetics, Part A, Vol. 173, No. 3, 01.03.2017, p. 784-789.

Research output: Article

Sepp, R, Hategan, L, Bácsi, A, Cseklye, J, Környei, L, Borbás, J, Széll, M, Forster, T, Nagy, I & Hegedűs, Z 2017, 'Timothy syndrome 1 genotype without syndactyly and major extracardiac manifestations', American Journal of Medical Genetics, Part A, vol. 173, no. 3, pp. 784-789. https://doi.org/10.1002/ajmg.a.38084
Sepp, Róbert ; Hategan, Lidia ; Bácsi, Attila ; Cseklye, Judit ; Környei, László ; Borbás, János ; Széll, Márta ; Forster, T. ; Nagy, István ; Hegedűs, Zoltán. / Timothy syndrome 1 genotype without syndactyly and major extracardiac manifestations. In: American Journal of Medical Genetics, Part A. 2017 ; Vol. 173, No. 3. pp. 784-789.
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