Gross phenotype in <i>Sh3pxd2b^nee</i> mutant mice.

<p><b>A,</b> Comparison of the lateral view of a 20-day-old male mutant mouse (left) and a wild-type littermate control mouse (right). The mutant mouse exhibits a domed and rounded skull, and a shortened nose. <b>B,C,</b> Macroscopic views of the tympanic membranes of an 11-day-old male mutant mouse (<b>B</b>) and a wild-type littermate male control mouse (<b>C</b>). The surface of the tympanic membrane is covered by thick, white exudate (arrow) in the mutant mouse ear, making the tympanic membrane adiaphanous and uneven (<b>B</b>). In the ear of the control mouse, the ossicles are clearly visible through the smooth, transparent tympanic membrane (<b>C</b>). <b>D,E,</b> Macroscopic views of the tympanic membranes of a 14-day-old male mutant mouse (<b>D</b>) and a wild-type littermate control mouse (<b>E</b>). The mutant mouse exhibits a relatively more protuberant malleus, which indicates that there is tympanic membrane retraction (<b>D</b>, arrow). The control mouse has a relatively even malleus and tympanic membrane, when compared to the mutant mouse (<b>E</b>). (M = mutant, WT = wild-type, m = malleus, tm = tympanic membrane). Scale bar, 200 µm.