Variation in growth of Apert syndrome models. Differences in growth between Fgfr2+/S252W and unaffected littermates (A, lateral view; B, superior view) and Fgfr2+/P253R and unaffected littermates (C, lateral; D, superior). For all views rostral is left, caudal is right. The linear distances pictured are limited to those whose growth from E17.5 to P0 differed significantly by ≥ 5% using α = 0.10 confidence limits. The magnitude of these differences in growth varies across the skull. Linear distances that grew significantly more (blue) and significantly less (white) in mutant mice are shown. Thin lines indicate linear distances whose growth was increased or decreased by 5-10% in mice carrying one of the two Fgfr2 mutations relative to their respective unaffected littermates; thick lines indicate linear distances whose growth differed by >10% between unaffected and mutant mice. Bone segmented from HRμCT images is shown as partially transparent to better visualize the growth differences. See supplementary videos for a full 360-degree rotation of differences in cranial growth between Fgfr2+/S252W mice and unaffected littermates [Additional file 8] and between Fgfr2+/P253R and unaffected littermates [Additional file 9].