A high-resolution radiation hybrid map of the proximal portion of mouse chromosome 5

Radiation hybrid (RH) mapping of the mouse genome provides a useful tool in the integration of existing genetic and physical maps, as well as in the o ngoing effort to generate a dense map of expressed sequence tags. To facili tate functional analysis of mouse Chromosome 5, we have constructed a high- resolution RH map spanning 75 cM of the chromosome. During the course of th ese studies, we have developed RHBase, an RH data management program that p rovides data storage and an interface to several RH mapping programs and da tabases. We have typed 95 markers on the T31 RH panel and generated an inte grated map, pooling data from several sources. The integrated RH map ranges from the most proximal marker, D51Mit331 (Chromosome Committee offset, 3 c M), to D5Mit326, 74.5 cM distal on our genetic map (Chromosome Committee of fset, 80 cM), and consists of 138 markers, including 89 simple sequence len gth polymorphic markers, 11 sequence-tagged sites generated from BAC end se quence, and 38 gene loci, and represents average coverage of approximately one locus per 0.5 cM with some regions more densely mapped. In addition to the RH mapping of markers and genes previously localized on mouse Chromosom e 5, this RH map places the alpha-4 GABA(A) receptor subunit gene (Gabra4) in the central portion of the chromosome, in the vicinity of the cluster of three other GABA(A) receptor subunit genes (Gabrg1-Gabra2-Gabrb1). Our map ping effort has also defined a new cluster of four genes in the semaphorin gene family (Sema3a, Sema3c, Sema3d, and Sema3e) and the Wolfram syndrome g ene (Wfs1) in this region of the chromosome. (C) 2000 Academic Press.