Neural tube defects (NTDs) are a group of birth defects that result from improper development of the spine, spinal cord, or brain during pregnancy. Spina bifida, in which some of the spinal cord bulges out through an opening in the spine, is most common. Neural tube defects occur in children of all ethnic backgrounds and in all countries.

Research studies have shown that a woman who takes folic acid supplements prior to and during pregnancy reduces her risk of having a child born with a neural tube defect. Since 1998 the United States has added folic acid to its enriched cereal grain products to help reduce NTDs.

The U.S. Centers for Disease Control and Prevention (CDC) examined birth data from 1995 to 2005 to see what effect adding folic acid to food may have had on the rate of NTDs. The CDC found that from the early postfortification period of 1999--2000 to the recent postfortification period of 2003--2005, the birth prevalence of spina bifida among infants born to mothers of all racial/ethnic populations decreased 6.9%. Among non-Hispanic black mothers, the prevalence decreased 19.8% in that same period, but no significant decrease was noted for infants with non-Hispanic white and Hispanic mothers.

The CDC states in the conclusion of its report, "Future public health efforts to reduce the prevalence of spina bifida should focus on subgroups of women with known risk factors for an NTD-affected pregnancy, such as obesity, Hispanic ethnicity, and certain genetic factors."

• More about folic acid fortification and neural tube defects
• What is spina bifida?
• Folic Acid FAQs

"Racial/Ethnic Differences in the Birth Prevalence of Spina Bifida---United States, 1995--2005." MMWR Weekly 57(2009): 1409-1413.

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Hemophilia A is the more common type of hemophilia. It results from a deficiency of coagulation Factor VIII. Hemophilia is inherited as an X-linked recessive disorder. This means that it almost always affects males.

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A rare disease occurs in less than 200,000 individuals in the United States, or less than 5 per 10,000 individuals in the European Union. Specialty drugs to treat rare diseases are known as "orphan drugs" because they treat such small numbers of people. In 2008 the U.S. Food and Drug Administration (FDA) approved several noteworthy orphan drugs, including some that are the first to treat a rare condition.

Jett Travolta, the 16-year-old son of John Travolta and Kelly Preston, died Friday, January 2, 2009, after apparently having a seizure in the bathroom and hitting his head on the bathtub. Jett was in the news when he was 2 years old after he became very ill with Kawasaki disease, which causes inflammation of the blood vessels throughout the body. Some researchers believe that Kawasaki disease is an autoimmune disorder stimulated by exposure to an environmental toxin. Kelly Preston has stated over the years that she believes Jett developed the disease due to exposure to household cleaners, fertilizers, and new carpeting they had installed in their home. Preston and Travolta, both practicing Scientologists, have said that a detoxification program based on their church's teachings helped improve Jett's health.

• More about Kawasaki disease
• MSN story about Jett's death

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