The squiggle tail ( squig ) mutation in mice is associated with a deletion in the mesenchyme homeobox 1 ( Meox1 ) gene

Objective We have taken a positional approach to assign the spontaneous squiggle tail ( squig ) mutation in mice to a specific gene defect. Results A large panel of backcross mice was produced and characterized to map squig to high genetic resolution on mouse Chromosome (Chr) 11. Two overlapping candidate genes that co-localized with squig ( Meox1 , for mesenchyme homeobox 1; and Gm11551 , which encodes a lncRNA located entirely within the first intron of Meox1 ) were fully sequenced to discover any squig -specific defects. This analysis revealed a 3195 bp deletion that includes all of Meox1 , Exon 1 but does not disrupt Gm11551 . We recommend that the squig mutation be renamed Meox1 squig , and suggest that this variant may offer an appropriate animal model for Klippel-Feil syndrome 2 (KFS2) in humans.