mortality/aging
• not all mice survive to term
|
craniofacial
• fusion of the atlas to the occipital bones is common
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• marked reduction in the second branchial arch
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limbs/digits/tail
• posterior expansion of both fore- and hindlimb buds at E9.5 and E10.5
• widened buds split into up to 3 extra buds but these extra buds appear to degenerate leaving only one to develop into a limb
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• at P0, 5 +/- 9.4 caudal vertebrae are present compared to 31 +/- 0.9 in wild-type mice
• some remnant vertebrae bodies are seen posterior to the lumbrosacral truncation
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skeleton
• fusion of the atlas to the occipital bones is common
|
• at P0, 5 +/- 9.4 caudal vertebrae are present compared to 31 +/- 0.9 in wild-type mice
• some remnant vertebrae bodies are seen posterior to the lumbrosacral truncation
|
• in all mice R1 is not attached to the sternum and in about half of the mice R2 in not attached to the sternum
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rib fusion
(
J:49154
)
• occasional posterior transformation of T7 to T8 (loss of attachment to the sternum)
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• at P0, anterior transformations of C1, C2,C3, and C7 are seen with varying levels of penetrance
• penetrance and expressivity of anterior, but not posterior, transformations are enhanced compared to Fgfr1tm2Jrt homozygotes
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embryo
• marked reduction in the second branchial arch
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• severe posterior deletions extends into the lumbrosacrumlumbrosacral level
• however, hind limbs and occasional remnants of vertebral bodies can be observed
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• anterior-posterior defects in lateral plate mesoderm patterning
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• posterior expansion of both fore- and hindlimb buds at E9.5 and E10.5
• widened buds split into up to 3 extra buds but these extra buds appear to degenerate leaving only one to develop into a limb
|
• expansion of the posterior neural fold at E9.5
|
• at E10.5, somites posterior to the hindlimb buds form but then appear to be degenerating at E12.5
|