Further studies on using multiple-cross mapping (MCM) to map quantitative trait loci.
We have completed whole-genome scans for quantitative trait loci (QTLs) associated with acute ethanol-induced activation in the six F(2) intercrosses that can be formed from the C57BL/6J (B6), DBA/2J (D2) , BALB/cJ (C), and LP/J (LP) inbred strains. The goal was to test the hypothesis that given the relatively simple structure of the laboratory mouse genome, the same QTLs will be detected in multiple crosses which in turn will provide support for the strategy of multiple-cross mapping (MCM). QTLs with LOD scores greater than 4 were detected on Chrs 1, 2, 3, 8, 9, 13, 14, and 16. Only for the QTL on distal Chr 1 was there convincing evidence that the same or at least a very similar QTL was detected in multiple crosses. We also mapped the Chr 2 QTL directly in heterogeneous stock (HS) animals derived from the four inbred strains. At G(19) the QTL was mapped to an approximately 3-Mbp interval and this interval was associated with a haplotype block with a largely biallelic structure: B6-L:C-D2. We conclude that mapping in HS animals not only provides significantly greater QTL resolution, at least in some cases it provides significantly more information about the QTL haplotype structure.
Malmanger
Barry
B
Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239-3098, USA.
Lawler
Maureen
M
Coulombe
Shannon
S
Murray
Rochelle
R
Cooper
Staci
S
Polyakov
Yekaterina
Y
Belknap
John
J
Hitzemann
Robert
R
D000818:Animals; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D000431:Ethanol / Q000494:pharmacology*; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D006239:Haplotypes / Q000235:genetics; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D018895:Microsatellite Repeats; D009043:Motor Activity / Q000187:drug effects / Q000235:genetics*; D040641:Quantitative Trait Loci
D005819:Genetic Markers; D000431:Ethanol