Initial findings on teratological and developmental relationships and differences between neural tube defects and facial clefting. First experimental results.

Unless genetically caused, the occurrence of neural tube defects and clefts of the lip, alveolus and palate are not associated. These malformations do, however, share some common causes, one of which is folic acid deficiency. Nevertheless, it is not known why a neural tube defect resulting from folic acid deficiency does not occur in combination with facial clefts. Based on animal experiments and a review of the literature, it is assumed that other factors--such as vitamin B6 deficiency--though clinically not diagnosed, can more often cause malformations.