Mapping Data

Experiment

• Experiment
  TEXT-QTL
• Chromosome
  13
• Reference
  J:71964 Juriloff DM, et al., Multifactorial genetics of exencephaly in SELH/Bc mice. Teratology. 2001 Oct;64(4):189-200
• ID
  MGI:2152532

Genes

Gene	Assay Type
D13Mit117
D13Mit91
D13Mit13
Lect2	reported elsewhere
D13Mit39
D13Mit193
Exen1	visible phenotype
Tfap2a	reported elsewhere
Jarid2	reported elsewhere
Fgd3	reported elsewhere
Msx2	reported elsewhere
Mxd3	reported elsewhere
Pitx1	reported elsewhere
Neurog1	reported elsewhere
Smad5	reported elsewhere
Ptch1	reported elsewhere
Tgfbi	reported elsewhere
Dhfr	reported elsewhere
Irx1	reported elsewhere
D13Bc1

Notes

• Experiment
  109 informative markers at an average spacing of 14 cM were typed in embryos from a (SELH/Bc x LM/Bc)F2 intercross to identify QTLs associated with exencephaly. Parental strain SELH/Bc exhibits a high frequency of exencephaly (10-30%) whereas normal parental strain LM/Bc exhibits 0.1% frequency of exencephaly. (SELH/Bc x LM/Bc)F1 hybrids exhibit low frequency of exencephaly (0.3%). A locus with significant linkage to exencephaly, Exen1, mapped to mouse Chromosome 13 from 30 cM - 40 cM (P<0.001 at D13Mit39). Fine mapping recombination breakpoints at Exen1 in 33 F2 embryos exhibiting exencephaly revealed strongest association at Lect2 and D13Mit13, approximately 35 cM - 37 cM. SELH/Bc-derived alleles appear to confer increased risk for exencephaly in a semidominant manner. Several candidate genes implicated in neural tube defect mutants map near Exen1 and include Tcfap2a, Jarid2, Msx2, Madh5, and Ptch. Other possible candidate genes in the region of Exen1 include Mad3, Pitx1, Neurog1, Tgfbi, Dhfr, and Irx1. Exen1 appears to interact with a locus on mouse Chromosome 11 at 63 cM suggestively linked to exencephaly (P = 0.063 at D11Mit10). Another suggestive locus maps to mouse Chromosome 5 at 78 cM (P = 0.02 at D5Mit168) but shows no interaction with Exen1. Possible candidate genes for the Chromosome 5 locus are Actb and Rac1.