Mapping Data

Experiment

• Experiment
  TEXT
• Chromosome
  X
• Reference
  J:111839 Chadwick LH, et al., Genetic control of x chromosome inactivation in mice: definition of the xce candidate interval. Genetics. 2006 Aug;173(4):2103-10
• ID
  MGI:3663132

Genes

Gene	Assay Type
Xic
DXMit168	PCR amplified length variant

Notes

• Experiment
  The X inactivation center, Xce, was refined using QTL mapping techniques. Seventy-eight Xce heterozygous females and 28 Xce homozygous females from a (C57BL/6J x CAST/EiJ)F2 intercross were genotyped for microsatellite markers spanning the genome at a 20cM resolution. Parental strain C57BL/6J carries an intermediate strength allele (Xce^b) whereas CAST/EiJ carries a strong allele (Xce^c). Given Xce alleles are in a heterozygous state, the weaker allele is more likely to be inactivated. A single locus on mouse Chromosome X was detected (LOD=12) indicating Xce is the only major locus influencing X chromosome inactivation choice.
  
  Xce was localized to a 2.3 cM interval between DXMit41 (39.6 cM) and DXMit171 (41.9 cM) by genotyping 528 (C57BL/6J x CAST/EiJ)F2 females and 127 (BALB/cByJ x CAST/EiJ)F2 females for markers on the X chromosome. Xce was further refined to a 1.85 Mb region of mouse Chromosome X between DXMit168 (96.3 Mb) and SNP-843 (98.1 Mb) by haplotype analysis of animals recombinant acrossthe DXMit41-DXMit171 interval. Progeny testing of X inactivation patterns in backcross animals confirmed the refined Xce interval.
  
  Autosomal modifiers of X inactivation were not detected after whole genome scan using 72 Xce heterozygous females and 79 heterozygous female embryos from a (C57BL/6J x CAST/EiJ)F2 intercross. A suggestive locus on mouse Chromosome 4 did not attain statistical significance upon further investigation.