Genetic screening of the canine connexin 40 gene in dogs with inherited cardiac conduction defects.
Connexin 40 (Cx40) is a gap-junction protein expressed in the heart where it mediates the coordinated electrical activation of the atria and ventricular conduction tissues, facilitates cell-to-cell adhesion, and provides pathways for direct intercellular communication. Recent studies have shown that Cx40 null mice have cardiac conduction abnormalities with a very high incidence of cardiac malformations in heterozygous (18%) and homozygous (33%) animals, indicating that Cx40 plays a vital role in cardiomorphogenesis. Since several inherited cardiac conduction defects have also been found in dogs, we hypothesized that the clinical findings are genetically linked to a tissue-specific mutation or mutations in the canine Cx40 gene. We therefore screened the Cx40 gene in dogs with inherited cardiac conduction defects for mutations. In this study, we have identified three heterozygous base changes (C384G, C402T, C837T) in the dogs screened and determined them to be synonymous mutations. These mutations, however, have recently been found in an unrelated group of normal dogs.
Lee
Shin-Aeh
SA
Section of Small Animal Internal Medicine, School of Veterinary Medicine, Kangwon National University, Chuncheon, Korea.
Lee
Joon-Seok
JS
Lee
Seung-Gon
SG
Lavulo
Lopeti
L
Cho
Kyoung-Oh
KO
Hyun
Changbaig
C
D000818:Animals; D001483:Base Sequence; D002448:Cell Adhesion / Q000235:genetics; D017630:Connexins / Q000235:genetics* / Q000378:metabolism; D004283:Dog Diseases / Q000235:genetics* / Q000378:metabolism; D004285:Dogs / Q000235:genetics* / Q000378:metabolism; D006329:Heart Conduction System / Q000196:embryology / Q000378:metabolism; D006330:Heart Defects, Congenital / Q000235:genetics* / Q000378:metabolism / Q000662:veterinary*; D051379:Mice; D008817:Mice, Mutant Strains; D008969:Molecular Sequence Data; D009154:Mutation; D038081:Organogenesis / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D000097003:Gap Junction alpha-5 Protein
D017630:Connexins; D000097003:Gap Junction alpha-5 Protein