Table 1. Igfbp7^−/− mice have significantly fewer terminal end buds and alveolar structures compared to the wild-type (+/+) glands.

Age	Igfbp7	Number of TEBsStructure	Ductal Tips(Branching)
3 weeks	+/+	76.0±4.0
	+/−	27.7±6.43
	−/−	25.0±9.85
6 weeks	+/+		200.7±25.03
	+/−		223.0±17.43
	−/−		135.0±38.63
11 weeks	+/+		475.3±45.24
	+/−		275.0±8.50
	−/−		156.7±13.28

Three inguinal glands each from the wild-type (+/+) mice or Igfbp7 heterozygous (+/−) or homozygous (−/−) mutant mice and analyzed for the number of terminal end buds (TEBs) and alveolar structures at 3 weeks, 6 weeks or 11 weeks of age. The two-tailed ANOVA analysis was used at 95% confidence intervals to analyze the data. The heterozygous and the homozygous knockout glands contain significantly fewer TEBs and alveolar structures (P<0.0001).