This association has biological plausibility especially for the Wnt pathway. First, non-canonical Wnt pathway is crucial for cell migration and LY2109761 development of organs of endodermal origin. There is indirect evidence for the involvement of the non-canonical Wnt pathway in the developing thyroid in mice, even though the canonical Wnt/beta-catenin pathway seems to be inactive during thyroid development in mice and humans. Second, as Wnt signaling is implicated in development and cancer, to find an association between Wnt pathway and thyroid ectopy makes biologically sense. Indeed, SFRPs have been associated with embryonic patterning, inhibition of meduloblastoma cell proliferation and inhibition of glioma cell motility. Inhibition of the Wnt pathway by Wnt5-a has also been shown to supress tumor activity in thyroid carcinoma. This study has several limitations. First, the expression profiles in tissue collected and analyzed postnatally may not reflect embryonic expression. Consequently, whether the differences we observed are causes or consequences of the ectopic location of the thyroid remains to be tested. Second, even though clusters of genes involved in histone and chromatin function have repressed expression in ectopic thyroids, we have not formally excluded a role of differential histone methylation or acetylation on differential gene expression in ectopic thyroids. Third, the arrays used for the CNVs and methylome analyses have their own limits in definition and genome coverage. Lastly, the sample number is small but our preliminary findings justify testing a larger number of samples. This study identifies interesting candidate pathways that may play important roles in the migration of the embryonic thyroid and provides a prototype approach for the study of congenital disorders difficult to explain by classical genetics. During fertilization in higher plants, pollen landing on the receptive stigma of the pistil germinates, producing a pollen tube that grows and carries male gametes to the embryo sac for final gamete fusion. Two basic processes take place during pollen tube growth, tube extension and orientation, which ensure that the pollen tube reaches the correct destination. The pollen tube extends via tip growth, during which polarized apical secretion results in unidirectional cell expansion. This provides an excellent example of polarized growth and an ideal model system for clarifying the processes of organization and regulation, thus attracting broad interest for several decades. Extensive studies have revealed that the dynamic extension and orientation process requires organization of the cell cytoskeleton, the deposition of the cell wall, and the balance of exocytosis and endocytosis. Recently, a great deal of attention has been given to the latter case, specifically, vesicle trafficking at the tube apex. Many vesicle-trafficking-related compartments have been characterized via electron microscopy and co-localization with the endocytic marker FM4-64. The potential markers of endosome compartments were used to visualize vesicle trafficking.