| Namespace | MPheno.ontology | Obsolete | false |
| description | failure to develop or maintain the unique club-shaped epithelial structure normally formed at the tip of the mammary duct at the onset of puberty (approximately 3 weeks of age in mouse) under the action of circulating hormones; normally, TEBs proliferate, ramify, and actively invade the fad pad to allow the formation of a complex branching structure; this process of branching morphogenesis concludes at about 10-12 weeks of age in mouse, when TEBs have traversed the length of the fat pad and a fully developed ductal tree has formed; absence of TEBs is often associated with reduced ductal outgrowth and impaired branching morphogenesis |
