Table 1. Frequency of occurrence of expression patterns for the fiZ transgene.

Stage	Tissue	Frequency
Embryo	Eye lens	2/5
	Vibrissae placodes	1/5
	Forebrain	1/5
	Forelimb ectoderm	1/5
	Forelimb AER	1/5
	Mammary gland mesenchyme	4/5
	Spinal cord	3/5
	hindbrain	4/5
Newborn and adult	Brain (different patterns)	3/5
	Spinal cord	0/5
	Other tissues	0/5

Expression territories which appear in more than two mouse lines are shown in boldface, the others being considered as possibly due to the influence of fiZ transgene insertion site. AER stands for Apical Ectodermal Ridge. Different expression sites in the newborn/adult brain are scored together as “brain”, but since they were not consistent in different transgenic lines, the precise regions have not been characterized in detail.