A single copy of Carbonic anhydrase 2 restores wild-type circadian period to carbonic anhydrase II-deficient mice

Kari L. Kernek, James A. Trofatter, Aimee R. Mayeda, Debomoy K. Lahiri, John R. Hofstetter

Research output: Contribution to journalArticle

5 Scopus citations


Carbonic anhydrase II (CA-II)-deficient mice have long circadian periods compared to their siblings with normal CA-II levels. The CA-II-deficient mice differ genetically from their siblings at proximal chromosome three, where the mutated carbonic anhydrase 2 gene sits on a small insert of DNA from the DBA/2J strain. The rest of the genome is that of the C57BL/6J strain. The goal of this study was to test the hypothesis that the null mutation in carbonic anhydrase 2 and the long circadian period phenotype were linked. In order to separate the effect of the null mutation in carbonic anhydrase 2 from the effect of DBA/2J alleles of other genes on the insert, two new lines of mice were studied. The first line, Kar, was developed from a CA-II-deficient mouse that had a fortuitous recombination restoring functional CA-II without affecting the rest of the DBA/2J insert. The second line was generated by breeding DBA/2J mice and C57BL/6J mice until they had the genomic composition of CA-II-deficient mice without the null mutation. Both lines of mice had circadian periods not different from C57BL/6J mice and shorter than CA-II-deficient mice. The phenotype of the new lines showed that the long circadian period characteristic of the CA-II-deficient mice arises when functional CA-II is absent, not when DBA/2J alleles are present on proximal chromosome three.

Original languageEnglish (US)
Pages (from-to)301-308
Number of pages8
JournalBehavior Genetics
Issue number2
StatePublished - Mar 1 2006



  • Carbonic anhydrase
  • Circadian
  • Genes
  • Mice
  • Period

ASJC Scopus subject areas

  • Genetics
  • Genetics(clinical)
  • Behavioral Neuroscience
  • Psychology(all)

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