Mapping Data

Experiment

• Experiment
  TEXT-QTL
• Chromosome
  19
• Reference
  J:141612 Reynolds AL, et al., Influence of a quantitative trait locus on mouse chromosome 19 to the light-adapted electroretinogram. Invest Ophthalmol Vis Sci. 2008 Sep;49(9):4058-63
• ID
  MGI:3820617

Genes

Gene	Assay Type
Lacrr1	visible phenotype
D19Mit10	PCR amplified length variant
D19Mit63	PCR amplified length variant
D19Mit1	PCR amplified length variant

Notes

• Experiment
  Genetic loci associated with single flash and flicker cone electroretinography (ERG) responses were mapped in backcross mice involving C57BL/6JOlaHsd and 129S2/SvHsd inbred parental strains. Linkage analysis was performed using 106 polymorphic markers spaced approximately 15 cM - 30 cM apart. Parental strain 129S2/SvHsd displays increased b-wave amplitude and increased single flash and flicker ERG a- and b-wave implicit times compared to parental strain C57BL/6JOlaHsd. Significant and suggestive linkagesto cone ERG responses were identified in the (C57BL/6JOlaHsd x 129S2/SvHsd)F1 x 129S2/SvHsd backross population (n=166).
  
  Linkage to five traits in the cone ERG response mapped to 47 cM on mouse Chromosome 19 near D19Mit10 in a subset of 20 backcross animals displaying the highest and lowest phenotypes. The same five traits also mapped to 57 cM near rs3023517. This locus was confirmed when all 166 backcross animals were analyzed and is named Lacrr1 (light adapted cone retinography response 1). The QTL displays linkage to the following ERG traits: single flash a-wave implicit time (LOD=10.7), flicker a-wave implicit time (LOD=16.4), single flash b-wave implicit time (LOD=20.7), flicker b-wave implicit time (LOD=23.6), single flash b-wave amplitude (LOD=23.2), and flicker b-wave amplitude (LOD=32.3). Homozygosity for 129S2/SvHsd=derived alleles at Lacrr1 confer decreased single flash and flicker b-wave amplitudes and increased single flash and flicker a- and b-wave implicit times. Lacrr1 appears to contribute 24% to 57% of the variance depending on the trait measured. Potential candidate genes located within the Lacrr1 QTL interval from D19Mit63 (24 cM) to D19Mit1 (52 cM) include Slit1, Sema4g, Kcnip2 (45 cM), Pax2 (43 cM), Pde6c, Rbp4 (38 cM), Pdcd11 andSmndc1. The last 2 genes display lower expression in retinal tissue from 129S2/SvHsd animals compared to C56BL/6JOlaHsd animals.
  
  Suggestive linkage to a-wave implicit time mapped to 22 cM on mouse Chromosome 4 near rs3667635 in a subset of 20 high and low responding (C57BL/6JOlaHsd x 129S2/SvHsd)F1 x 129S2/SvHsd backcross mice. This locus was not detected when the full set of backcross animals (n=166) was analyzed.
  
  Suggestive linkage to flicker b-wave implicit time mapped to 56 cM on mouse Chromosome 17near rs4231722 in 20 high and low responding (C57BL/6JOlaHsd x 129S2/SvHsd)F1 x 129S2/SvHsd backcross mice but disappeared when all 166 backcross animals were analyzed.
  
  When the initial dataset of 20 phenotypically extreme backcross animals was reanalyzed controlling for Lacrr1, a suggestive association between single flash and flicker b-wave amplitude and Snca (29 cM) on mouse Chromosome 6 was detected. Flicker a-wave implicit time also showed suggestive linkage to rs3693589 at 44 cM on mouse Chromosome 13. Both of these loci disappeared when all 166 backcross animals were analyzed.