Mapping Data

Experiment

• Experiment
  TEXT-QTL
• Chromosome
  12
• Reference
  J:91543 Wolf N, et al., Quantitative trait locus mapping for age-related cataract severity and synechia prevalence using four-way cross mice. Invest Ophthalmol Vis Sci. 2004 Jun;45(6):1922-9
• ID
  MGI:3052181

Genes

Gene	Assay Type
Lnopy2	visible phenotype
D12Mit34	PCR amplified length variant
Vsx2	reported elsewhere

Notes

• Experiment
  Genome scan was performed on 510 animals from a four-way (BALB/cJ x C57BL/6J)F1 x (C3H/HeJ x DBA/2J)F1 cross to identify QTLs associated with age-related cataracts and synechia. Animals were assessed for lens opacity and synechia using slit lamp examination at 18- and 24-months of age. A total of 188 polymorphic loci were genotyped. 96 markers detect maternal alleles (BALB/cJ and C57BL/6J) and 92 markers detect paternal alleles (C3H/HeJ and DBA/2J).
  
  No linkage was found for lens opacity at 18 months of age. At 24 months of age linkage to lens opacity mapped to 49.6 cM on mouse Chromosome 4 (D4Mit155, P=0.001) and to 29 cM mouse Chromosome 12 (D12Mit34, P=0.28). These QTLs are named Lnopy1 (lens opacity 1) and Lnopy2, respectively. DBA/2J-derived allele confers increased lens opacity at Lnopy1 compared to C3H/HeJ, and C57BL/6J-derived alleles confer increased lens opacity at Lnopy2 compared to BALB/cJ. Suggestive linkage to lens opacity mapped to 61 cM on mouse Chromosomes 5 (D5Mit25, P=0.06) and 2.4 cM on mouse Chromosome 11 (D11Mit2, P=0.042). These loci appear to have additive effects. Animals inheriting DBA/2J-derived at Lnopy1, C57BL/6J-derived alleles at Lnopy2, and C3H/HeJ-derived alleles at the chromosome 11 locus exhibit the highest incidence and severity of cataracts. Potential candidate genes Tyrp1 (38 cM), Foxe3 (49.6 cM), and Prdx1 (47 cM) map to the Lnopy1 interval and play a role in eye disease. Potential candidate gene Chx10 (38 cM) maps to the Lnopy2 interval. Crybb2 (60 cM) is a potential candidate gene for the chromosome 5 locus.
  
  A broad region of mouse Chromosome 4 spanning 20 cM - 67 cM (D4Mit55, D4Mit84, D4Mit170) is associated with cataract severity (P<0.001). This locus is named Ctrcts (cataract severity). DBA/2J-derived alleles confer increased cataract severity compared to C3H/HeJ-derived alleles. Potential candidate gene Galt (20 cM) maps to this region.
  
  Linkage to synechia in aged mice mapped to two loci on mouse Chromosome 4 at 17 cM (D4Mit55, P=0.001) and 38 cM (D4Mit84, P=0.001) and to a locus on mouse Chromosome 1 at 62 cM (D1Mit493, P=0.006). These loci are named Synch1, Synch2, and Synch3, respectively and appear to act additively. Animals inheriting DBA/2J-derived alleles at Synch3 and Synch1 and BALB/cJ-derived alleles at Synch2 exhibit the highest incidence of synechia. Synechia was observed with higher incidence in aged (24 month old) male mice compared to aged female mice.