If there is failure of migration of the neural crest cells to the facial region during prenatal development,_____ can develop in the embryo.

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If there is failure of migration of the neural crest cells to the facial region,Treacher Collins syndrome develops in the embryo.This results in failure of specific areas of orofacial development,presenting with downward slanting eyes,underdeveloped zygomatic bone,drooping lateral lower eyelids,and conductive hearing loss,with malformed or absent ears as well as dental developmental disturbances such as micrognathia,anodontia,and enamel dysplasia.Ectodermal dysplasia involves the abnormal development of one or more structures from ectoderm.Fetal alcohol syndrome is an example of the result of a teratogenic drug effect of high levels of ethanol ingested by a pregnant female during the embryonic period.Down syndrome occurs when an extra chromosome number 21 is present after meiotic division,leading to certain orofacial features.

If There Is Failure of Migration of the Neural Crest