Axtofa9^L2/Ibg
QTL Variant Detail

Summary

• QTL variant: Axtofa9^L2/Ibg
• Name: anxiety-open field activity 9; L2/Ibg
• MGI ID: MGI:3041592
• QTL: Axtofa9 Location: unknown Genetic Position: Chr7, Syntenic

Variant origin

• Strain of Specimen: L2/Ibg

Variant description

• Allele Type: QTL
• Inheritance: Not Specified

Notes

Mapping and Phenotype information for this QTL, its variants and associated markers

J:70479

QTL Reference Notes

DeFries strains: QTL were mapped in two large F2 intercrosses from four lines derived from a replicated selection experiment for open-field activity, an animal model for susceptibility to anxiety. The foundation for the selection experiment consisted of an F3 generation derived from a cross between inbred lines, BALBc/J and C57BL/6J. Ten F3 litters that contained at least two males and females were chosen at random. The most active male and female within each litter were selected to become the progenitors of one selected line, termed H1. The least active male and female from each of the same ten litters were selected to serve as progenitors of a low activity line, L1. The same selection procedure was applied to members of a second randomly chosen group of 10 F3 litters as parents for replicate selected lines H2 and L2. The resulting progeny represented the first selected generation. Within the two high lines the most active male and female were selected from each litter, whereas the least active male and female were selected from each litter in the two low lines.Thirty generations of selection were completed and in generation 30 open field activity scores of the high lines were 30 times greater than those of the low lines. Following the suspension of selection the lines were randomly mated within line for 18 generations and then inbred using brother-sister mating.

The initial cross was of 815 mice in the (H1 x L1) cross and of 821 mice in the (H2 x L2) cross. All of the animals were genotyped with all markers, a total of 128,500 genotypes. The results for mapping open field behaviors, behaviors in the the elevated plus maze and in the light-dark box in the two replicated crossed were obtained and compared in tables 1, 3 and 4. Haplotype information and the direction of effect of each QTL allele were used to confirm that the QTL mapped in the two crosses lie in the same chromosomal regions, but authors were unable to determine whether QTL in the two crosses represented the same genes.

03.12.2016 Curator Note: We have assigned offical nomenclature to the significant QTL (LOD=3.2) identified in each cross, (H1 x L1) and (H2 x L2). We have also assigned offical nomenclature to the significant QTL identified when cross data was combined if a significant QTL was not also identified in either of the two independent crosses.

In the (H1 x L1)F2 cross the following anxiety related QTL mapped to Chromosome 7:

Axtofa3, anxiety-open field activity 3, LOD=7.6 at 66 cM, accounting for 6.5% of trait variance, Table 1;

Axtepm12, anxiety-elevated plus maze 12, closed arms, LOD=11.6% at 50 cM, accounting for 10.1% of trait variance, Table 4.

In the (H2 x L2)F2 cross the following anxiety related QTL mapped to Chromosome 7:

Axtofa9, anxiety-open field activity 9, LOD=7.0 at 50 cM, accounting for 6.0% of trait variance, Table 1;

Axtofd2, anxiety-open field defecation 2, LOD=4.0 at 42 cM, accounting for 3.1% of trait variance, Table1;

Axtepm13, anxiety-elevated plus maze 13, closed arms, LOD=6.0 at 52 cM, accounting for 4.8% of trait variance.

References

• Original: J:70479 Turri MG, et al., Quantitative trait locus mapping in laboratory mice derived from a replicated selection experiment for open-field activity. Genetics. 2001 Jul;158(3):1217-26
• All: 1 reference(s)