Genetic linkage study

Abstract

Ikeda et al. performed a genome-wide linkage study using 16 Japanese families with moyamoya disease and 371 microsatellite markers [1]. In the study 13 of 16 families had sibling cases and the rest of them included parent-children transmission of the disease. Maximum nonparametric linkage (NPL) score of 3.4 was found at the marker D3S3050. NPL score of greater than 3.0 was observed at the three microsatellite markers, D3S2387, D3S3050, and D3S1560, which are located on chromosome 3p24.2-p26 (Fig. 1). In moyamoya disease, abnormal vascular formation is observed mainly in brain. Marfan syndrome is an extracellular matrix disorder with cardinal manifestations in the cardiovascular and skeleton systems. Moyamoya-like angiographic findings are sometimes associated with Marfan syndrome. Most patients with Marfan syndrome have mutations in fibrillin gene (FRN) on chromosome 15q21 [2]. The second locus for Marfan syndrome has been mapped at chromosome 3p25-24.2 [3]. Recently, TGFBR2, a putative tumor-suppressor gene implicated in several malignancies, has been identified for the second gene for Marfan syndrome [4]. Mutational analysis of TGFBR2 in patients with moyamoya disease has not been reported. Yamamoto et al. hypothesized that paternally imprinted gene might be associated with this disorder because of a high incidence of maternal inheritance in familial moyamoya disease. Although they screened genes with monoallelic expressions on chromosome 3, no imprinting gene was identified in this region [5]. © 2010 Springer-Verlag Tokyo.