title: A novel nonsense mutation in SCN9A in a Moroccan child with congenital insensitivity to pain.
abstract: BACKGROUND
  Congenital insensitivity to pain is a rare autosomal recessive disease. Individuals who are diagnosed with congenital insensitivity to pain usually present severely impaired pain perception, and in some cases, they also manifest a decreased sense of smell (anosmia). This disease is caused by loss of function mutations affecting the SCN9A gene, which encodes the voltage-gated sodium channel Nav1.7. It is noteworthy that nearly every mutation linking this particular channel to congenital insensitivity to pain has been demonstrated to underlie the translation of a truncated protein.
  
  
  METHODS
  Complete sequencing of the SCN9A gene in a Moroccan 3-year-old child with congenital insensitivity to pain.
  
  
  RESULTS
  We identified a homozygous nonsense mutation (c.4795C>T) in exon 27, that results in codon stop in the amino acid (p.R1599X).
  
  
  CONCLUSIONS
  In this report we present a previously unreported homozygous nonsense mutation present in a consanguineous Moroccan congenital insensitivity to pain patient with anosmia. The identification of this mutation extends the spectrum of mutations affecting the Nav1.7 channel, and it confirms earlier studies that established Nav1.7 roles in nociception and the sense of smell.
authors.affiliation: Département de Génétique Médicale, Institut National d'Hygiène, Rabat, Morocco. Electronic address: mariamansouriG@hotmail.fr.
authors.forename: Maria
authors.initials: M
authors.lastname: Mansouri
authors.affiliation: Département de Génétique Médicale, Institut National d'Hygiène, Rabat, Morocco.
authors.forename: Siham
authors.initials: S
authors.lastname: Chafai Elalaoui
authors.affiliation: Neurology and Neurosurgery Department, McGill University, Montréal, Quebec, Canada; Pathology and Cell Biology, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Bouchra
authors.initials: B
authors.lastname: Ouled Amar Bencheikh
authors.affiliation: Service d'odontologie pédiatrique, Faculté de médecine dentaire, Université Mohammed V Souissi, Rabat, Morocco.
authors.forename: Mohamed
authors.initials: M
authors.lastname: El Alloussi
authors.affiliation: Neurology and Neurosurgery Department, McGill University, Montréal, Quebec, Canada; Pathology and Cell Biology, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Dion
authors.affiliation: Département de Génétique Médicale, Institut National d'Hygiène, Rabat, Morocco; Centre de génomique humaine, Faculté de Médecine et de Pharmacie de Rabat, Université Mohammed V Souissi, Rabat, Morocco.
authors.forename: Abdelaziz
authors.initials: A
authors.lastname: Sefiani
authors.affiliation: Neurology and Neurosurgery Department, McGill University, Montréal, Quebec, Canada; Montreal Neurological Institute and Hospital, McGill University, Montréal, Quebec, Canada.
authors.forename: Guy A
authors.initials: GA
authors.lastname: Rouleau
mesh_terms: D002675:Child, Preschool; D018389:Codon, Nonsense / Q000235:genetics*; D003241:Consanguinity; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D009018:Morocco; D062556:NAV1.7 Voltage-Gated Sodium Channel / Q000235:genetics*; D000699:Pain Insensitivity, Congenital / Q000235:genetics*
chemical_list: D018389:Codon, Nonsense; D062556:NAV1.7 Voltage-Gated Sodium Channel; C486866:SCN9A protein, human
keywords: SCN9A; anosmia; congenital insensitivity to pain; novel mutation