116 страниц. 2011 год. LAP Lambert Academic Publishing The neural tube is the embryonic precursor of the brain and the spinal cord. Building a neural tube is an extremely complex phenomenon where cells need to change in shape, migrate and differentiate to form a hollown tube from a flat sheet of thickened epithelial cells (the neural plate). The normal closure of the neural plate occurs very early in human pregnancy from day 21 until day 28 following conception or 1 weak after the expected menstruation. Abnormal closure of the neural plate results in neural tube defects (NTDs). The orrelation between the birth of NTD affected children and the maternal polymorphisms of two genes related to the folate metabolic pathway, studied methylenetetrahydrofolate-dehydrogenase (MTHFD1) 1958 (G>A) and methionine synthase polymorphisms MTR 2756 (A>G) and MTR 2758(C>G) in the Jordanian population have been examined in this original study.