Figure 2: Representative skeletal phenotypes of newborns of the Hoxa13;Hoxd11-13;Gli3 allelic series. Digit number (indicated for the Gli3XtJ/XtJ condition) increases as distal Hox dose is reduced. When only one functional copy of Hoxa13 remains (right column), the tip of the digits is connected by a continuous band of ossified (red) and cartilaginous (blue) tissue rimming the distal border of the limb and becoming more conspicuous as Gli3 copies are removed. Figure and legend from Sheth et al. 2012.