Population-based and family-based association studies of an (AC)n dinucleotide repeat in alpha-7 nicotinic receptor subunit gene and schizophrenia

Schizophr Res. 2006 Jun;84(2-3):222-7. doi: 10.1016/j.schres.2006.02.012. Epub 2006 Mar 24.


The human alpha-7 neuronal nicotinic receptor subunit (CHRNA7) gene, located at chromosome 15q13.2, represents a strong candidate gene for schizophrenia. We have examined an (AC)n dinucleotide repeat in intron 2 of the CHRNA7 gene, which was previously shown to be strongly linked with schizophrenia, using both population-based and family-based association studies. In the population-based study, no significant differences between the genotype and allele frequency distributions in schizophrenia patients and control subjects were observed after correction for multiple testing, although a nominally significant association between the most common allele and schizophrenia was observed (P = 0.023, uncorrected for multiple testing). In the family-based study, there is no significant over-transmission (Transmitted/Non-transmitted: 61/50) of the same allele in 160 family trios. Overall, our results do not support a major role for the (AC)n dinucleotide repeat in schizophrenia susceptibility in Han Chinese. Further large-scale genetic studies based on a set of single nucleotide polymorphisms (SNPs) that fully characterize the linkage disequilibrium patterns at the CHRNA7 gene are necessary to determine the relevance of this gene as a risk factor for schizophrenia susceptibility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alleles
  • Asians / genetics
  • Chromosomes, Human, Pair 15 / genetics
  • DNA Primers / genetics
  • Dinucleotide Repeats
  • Female
  • Genetic Predisposition to Disease
  • Genotype
  • Humans
  • Male
  • Protein Subunits
  • Receptors, Nicotinic / genetics*
  • Risk Factors
  • Schizophrenia / epidemiology
  • Schizophrenia / genetics*
  • alpha7 Nicotinic Acetylcholine Receptor


  • Chrna7 protein, human
  • DNA Primers
  • Protein Subunits
  • Receptors, Nicotinic
  • alpha7 Nicotinic Acetylcholine Receptor