Trsp^fl/fl Col2a1-Cre mice exhibit runting and a shortened life-span.

<p>Frontal (A) and lateral (B) views of representative 4 wk old <i>Trsp^fl/fl Col2a1-Cre</i> and control mice. Compared to the littermate control, the <i>Trsp^fl/fl Col2a1-Cre</i> animal is runted, with hypomorphic ears and a shortened snout. (C) Lengths (from nose tip to base of tail) of groups of mice taken either at 1 day of age (n = 7 <i>Trsp^fl/fl Col2a1-Cre</i>, n = 4 <i>Trsp^fl/fl</i>), or at between 3.5–4 weeks of age (n = 9 <i>Trsp^fl/fl Col2a1-Cre</i>, n = 8 <i>Trsp^fl/fl</i>). While lengths of control and experimental mice were similar in the immediate post-natal period, by 3.5–4 weeks their lengths had diverged significantly. Data are mean+/−SEM. (D) Survival rates of mice followed for up to 7 weeks of age (n = 17 <i>Trsp^fl/fl Col2a1-Cre</i>; n = 18 <i>Trsp^fl/fl</i>).