title: Ménière's Disease: Molecular Analysis of Aquaporins 2, 3 and Potassium Channel KCNE1 Genes in Brazilian Patients.
abstract: Ménière's disease (MD) is a complex disease of unknown etiology characterized by a symptomatic tetrad of vertigo, hearing loss, tinnitus, and aural fullness. In addition to factors related to homeostasis of the inner ear, genetic factors have been implicated in its pathophysiology, including genes related to the transport of water and ionic composition maintenance of the endolymph, such as the aquaporin genes AQP2 and AQP3, and the potassium channel gene KCNE1. The aim of this study was to identify polymorphisms of these genes and determine their association with clinical characteristics of patients with MD.
  
  
  
  A case-control genetic association study was carried out, including 30 patients with definite Ménière's disease and 30 healthy controls. The coding regions of the target genes were amplified from blood samples by polymerase chain reaction (PCR), followed by direct sequencing. The associations of polymorphisms with clinical characteristics were analyzed with logistic regression.
  
  
  
  Five polymorphisms were identified: rs426496 in AQP2; rs591810 in AQP3; and rs1805127, rs1805128, and rs17173510 in KCNE1. After adjustment, rs426496 was significantly associated with tinnitus during the initial crisis and with altered electronystagmography, and rs1805127 was significantly associated with nephropathy.
  
  
  
  The genetic variant rs426496 in AQP2; rs591810 in AQP3 and rs1805127, rs1805128, and rs17173510, in KCNE1 were found in patients with Ménière's disease. The polymorphism rs426496, in AQP2, is associated with tinnitus at the onset of Ménière's disease and altered electronystagmography. In addition, rs1805127, in KCNE1, is associated with the presence of nephropathy.
authors: *Department of Otorhinolaryngology and Head and Neck Surgery, Federal University of São Paulo, São Paulo †Human Molecular Genetics Laboratory, State University of Campinas, Campinas, Brazil.
authors: Karen de Carvalho
authors: Kde C
authors: Lopes
authors: Edi Lúcia
authors: EL
authors: Sartorato
authors: Sueli M
authors: SM
authors: da Silva-Costa
authors: Nadya Soares
authors: NS
authors: de Macedo Adamov
authors: Fernando Freitas
authors: FF
authors: Ganança
mesh_terms: D000328:Adult; D051399:Aquaporin 2 / Q000235:genetics*; D051400:Aquaporin 3 / Q000235:genetics*; D001938:Brazil; D016022:Case-Control Studies; D004584:Electronystagmography; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D007674:Kidney Diseases / Q000235:genetics; D016015:Logistic Models; D008297:Male; D008575:Meniere Disease / Q000235:genetics*; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D024642:Potassium Channels, Voltage-Gated / Q000235:genetics*
chemical_list: C496023:AQP2 protein, human; C496027:AQP3 protein, human; D051399:Aquaporin 2; C489622:KCNE1 protein, human; D024642:Potassium Channels, Voltage-Gated; D051400:Aquaporin 3