Rho GTPase Activating Protein 11B (ARHGAP11B)

The ARHGAP11B and ARHGAP11A genes appear to be imbedded in BP4 and BP5, respectively. The CHRNA7 gene encodes the α7 subunit of the neuronal nicotinic receptor, which is a homopentameric synaptic ion channel protein. Although there are reports of genetic linkage to this region for juvenile myoclonic epilepsy and for rolandic epilepsy, these results do not implicate the CHRNA7 gene specifically any more that the immediate neighbouring genes. There are numerous publications suggesting a possible role for the CHRNA7 gene in schizophrenia as reviewed elsewhere. There is a CHRFAM7A fusion gene embedded in BP4 with an additional copy possibly imbedded in BP5 on some chromosomes, but the function of this gene, if any, is unclear. The fusion gene includes exons 5–10 of CHRNA7 fused to five exons of gene family member 7A (FAM7A).