Analysis Tools
mortality/aging
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• embryos die from mid to late gestation
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embryo
sirenomelia
(
J:67399
)
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• observed in 20% of fetuses
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• seen in surviving late stage embryos
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• in mildly affected embryos, the urogenital sinus is hypoplastic
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• the mesonephric and paramesonephric ducts merged prematurely within a hypoplastic urogenital sinus
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spina bifida
(
J:67399
)
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• lack of neural tube closure in the posterior region noted in one embryo
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• enlarged r4 is observed at E9.5
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• expression studies suggest that r2 and r3 have adopted characteristics of a more posterior fate
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nervous system
spina bifida
(
J:67399
)
|
• lack of neural tube closure in the posterior region noted in one embryo
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• enlarged r4 is observed at E9.5
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• expression studies suggest that r2 and r3 have adopted characteristics of a more posterior fate
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exencephaly
(
J:67399
)
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• observed in some embryos; variable expressivity
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• distal nerve fiber is abnormally pattered
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• the maxillary branch is abnormally wide
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• the opthalamic branch is reduced and some of the fibers are either misrouted toward the maxillary branch or form an ectopic branch
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limbs/digits/tail
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• hindlimbs are twisted to the left and/or are mispositioned, but are otherwise similar to controls
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sirenomelia
(
J:67399
)
|
• observed in 20% of fetuses
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short tail
(
J:67399
)
|
• truncations are usually seen in conjuction with spina bifida
• disorganized neural tissue outgrowths within truncated tail rudiments are common
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curly tail
(
J:67399
)
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• tail is frequently twisted and truncated
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cardiovascular system
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• dilated heart cavity and/or pericardial balooning seen at E8.5-E9.5
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• imperfectly looped heart tube seen at E8.5-E9.5
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• pericardial balooning seen at E8.5-E9.5
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renal/urinary system
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• in severely affected embryos, a single medial kidney is located between the gonads, with an ectopic secondary rudimentary kidney present that consists of a few metanephric tubules
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pelvic kidney
(
J:67399
)
|
• in some embryos, mild variable defects seen include posterior fusions of the kidneys (horseshoe kidney)
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• the mesonephric and paramesonephric ducts merged prematurely within a hypoplastic urogenital sinus
• a hypoplastic genital tubercle is present with a poorly developed urethral groove
• urogenital ducts and ureter buds end blindly when sirenomelia also present
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digestive/alimentary system
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• in mildly affected embryos, the hindgut ends as a blind ampulla within the wall of the abnormal urogenital sinus
• the caudal portion of the hindgut (presumptive rectum) is missing
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reproductive system
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• the mesonephric and paramesonephric ducts merged prematurely within a hypoplastic urogenital sinus
• a hypoplastic genital tubercle is present with a poorly developed urethral groove
• urogenital ducts and ureter buds end blindly when sirenomelia also present
|
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• a hypoplastic genital tubercle is present with a poorly developed urethral groove
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skeleton
rib fusion
(
J:67399
)
|
• vertebral cartilage elements are abnormal caudal to the first lumbar vertebra
• the tail rudiment contains condensations
• in severely affected embryos, the vertebral column is truncated caudal to L1
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• variable penetrance of C1 vertebral transformation to a more posterior vertebra fate
• variable penetrance of C2 vertebral transformation to a more posterior vertebra fate
• C7 vertebra consistently adopted a thoracic vertebra fate and harbors a full pair of ribs
• the anterior tuberculum is located on C5 instead of C6, indicating a posterior transformation
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growth/size/body
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• abdomenoschisis
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