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Old 12-25-2009
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Default Derivative of Parathyroid vs Parafollicular C-Cells of the Thyroid

Let me get this straight, according to First Aid, Parathyroid is derived from Endoderm, whereas the parafollicular C-Cells of the thyroid is from Neural crest.

But is there a component of parathyroid that is from the neural crest as well? Because I thought that in Multiple Endocrine Neoplasia (MEN), the one common thing that all of the neoplasias share is that they are from the neural crest cells, and hence, shouldn't parathyroid be from neural crest cells as well?
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Old 12-26-2009
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Default MEN and neural crest origin

Multiple Endocrine Neoplasia does not originate from neural crests. It originates from a tumor suppressor gene mutation with two hits needed to manifest the clinical features.
I think your confusion comes from the fact that in MEN2B you have medullary carcinoma of the thyroid, mucosal neuromas, and neuroblastoma which are all coming from neural crests. But remember that MEN2B does not have hyperparathyroidism. Parathyroid hyperplasia is only seen in MEN1 and MEN2A.
So parathyroid glands definitely come from the third & fourth pharyngeal pouches and parafollicular cells migrate to the area as with other neural crest originated tissues.
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Old 12-26-2009
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Ahh I see. Thanks.
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embryology , endocrine

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