7q11 Region unrelated to dominantly inherited intracranial aneurysm in Korean families

Intracranial aneurysms (IAs), abnormal bulging of one of arteries in the brain, are caused by many environmental and genetic factors. One of the major causes leading to complex diseases are known to be genetic factors. In an attempt to elucidate the genetic factor contributing the etiology of IAs, several genetic loci for IA have been reported recently. Among them, 7q11 locus was supposed to be a disease-related locus for IAs in Asia, and the locus was further confirmed in the United States. By careful investigation of the inheritance pattern of 315 IA patients at Chonbuk National University Hospital, we recruited 4 families inheriting IAs dominantly. Thorough linkage analysis on chromosome 7 was conducted to confirm whether 7q11 locus of IAs are present m Korean population. We employed a parametric method for linkage analyses and calculated two-point and multipoint LOD scores using LINKAGE package (v5.1). Total two-point LOD scores (θ=0) for D7S502 and D7S669 markers on 7q11 region were -5.282 and -5.141, respectively. And a maximum multipoint LOD score was also negative on 7q11 locus. Our results clearly imply that Korean and Japanese have different genetic locus for IA, even though it is widely believed that Japanese and Korean are genetically homogenous in many aspects.