Radiation hybrid maps of Medaka chromosomes LG 12, 17, and 22.
The Medaka is an excellent genetic system for studies of vertebrate development and disease and environmental and evolutionary biology studies. To facilitate the mapping of markers or the cloning of affected genes in Medaka mutants identified by forward-genetic screens, we have established a panel of whole-genome radiation hybrids (RHs) and RH maps for three Medaka chromosomes. RH mapping is useful, since markers to be mapped need not be polymorphic and one can establish the order of markers that are difficult to resolve by genetic mapping owing to low genetic recombination rates. RHs were generated by fusing the irradiated donor, OLF-136 Medaka cell line, with the host B78 mouse melanoma cells. Of 290 initial RH clones, we selected 93 on the basis of high retention of fragments of the Medaka genome to establish a panel that allows genotyping in the 96-well format. RH maps for linkage groups 12, 17, and 22 were generated using 159 markers. The average retention for the three chromosomes was 19% and the average break point frequency was approximately 33 kb/cR. We estimate the potential resolution of the RH panel to be approximately 186 kb, which is high enough for integrating RH data with bacterial artificial chromosome clones. Thus, this first RH panel will be a useful tool for mapping mutated genes in Medaka.
Su
Feng
F
The Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
Osada
Yumi
Y
Ekker
Marc
M
Chevrette
Mario
M
Shimizu
Atsushi
A
Asakawa
Shuichi
S
Shiohama
Aiko
A
Sasaki
Takashi
T
Shimizu
Nobuyoshi
N
Yamanaka
Toshiyuki
T
Sasado
Takao
T
Mitani
Hiroshi
H
Geisler
Robert
R
Kondoh
Hisato
H
Furutani-Seiki
Makoto
M
D000818:Animals; D002875:Chromosomes / Q000235:genetics*; D005819:Genetic Markers; D016678:Genome / Q000235:genetics; D009990:Oryzias / Q000235:genetics*; D021101:Radiation Hybrid Mapping
D005819:Genetic Markers