The neural tube is a tubular structure induced from the ectoderm by the mesoderm during gastrulation in the embryo. It is the precursor to the vertebrate nervous system and is patterned during embryogenesis to form the brain, the spinal cord and most of the nerves of originating in the central nervous system. In the absence of a neural tube vertebrates die during embryonic development as they have no consciousness, perception, autonomic or motor functions of any variety.

The neural tube forms from the neural plate which begins to develop 16 days after conception. Once formed neurulation occurs with the tube being fully closed by 27 days after conception. At this point the brain and spinal cord have already begun to develop.

No, vertebrate neural tube development can be manipulated, the early embryo grafting experiments performed by Spemann and Mangold demonstrated that but at present therapeutic manipulation is not possible.

Folic acid (vitamin B 9) is important for the production of healthy cells however why folic acid deficiencies are associated with neural tube disorders (NTDs) is unclear at present. There are several ways of attaining adequate amounts of folic acid. 

1. Taking multivitamin supplements or single vitamin tablets which can be found at most pharmacies and some local stores.
2. Eating a severing of breakfast cereals which have 100% of the daily value (DV) of folic acid per serving every day. Such cereals include Kellogg’s®All-Bran®Original and Kellogg’s®Special K®, a comprehensive list of cereals can be found at https://www.cdc.gov/ncbddd/folicacid/cereals.htm. Remember to check the label on the side of the box that should say “100%” next to folic acid.

NTDs involving the failure of the neural tube to close happen within the first few weeks of pregnancy often before the mother even knows that she is pregnant. By this point it can often be to late to prevent NTDs connected with folic acid deficiencies from occurring. It is therefore vital that any woman trying to conceive ensures she is consuming adequate amounts of folic acid. It is recommended now that all women of child baring age take folic acid supplements.

No in a large number of cases it can be prevented but once it has occurred, although surgery can help, varying levels of disability will occur.

All pregnant women are offered the chance of screening but it is optional and couples can decline it. The screens are carried out by the NHS and there is no charge for testing. The testing is split into two stages an initial screening test and then a follow up diagnostic test can be offered depending on the outcome of the first test. The screening test is not conclusive and a positive test for spina bifida does not mean the child will have it, it just means that there is an increased risk. The second definitive test is then required to confirm the presence of the abnormality. For a spina bifida screening, a substance called alphafetoprotein (AFP) is measured from a small sample of the mother's blood taken between 15 and 20 weeks of pregnancy. 85% of pregnancies with spina bifida have higher than normal levels of AFP, but so also do some perfectly normal pregnancies.   

If you have had a previous pregnancy with NTDs or have a family history of NTDs then you run a higher risk of having a child with NTDs. Additional risk factors include women who have type 2 diabetes, gastrointestinal malabsorption disorders or taking drugs that interfere with folic acid metabolism such as antiepileptic drugs.