Figure 3.

Relationship between the sizes of the penian bone, the baculum, and digit IV in HoxD and HoxA mutant juvenile male mice. (A) Forelimb digit IV (Left) and the penis (Right) of 11-day-old juvenile sibling males were isolated, cleared, and compared. The genotypes are indicated on the right. An extreme reduction of the baculum was observed in mice of the HoxD^Del/Del;Hoxa-13^+/− genotypes, i.e., mice with the shortest digits. In such specimen, the baculum was ill-formed and barely half of the expected length and thickness. (B) As control for the overall size of the mice, the scapula of the same two genotypes are shown. Although a noticeable reduction of the scapula in HoxD^Del/Del;Hoxa-13^+/− animals indicate their general shorter statures, this reduction was much less drastic than that observed for the penian bone, which was almost absent.