SAMPLE BANK UP AND RUNNING What can a drop of blood tell us? It may be a crystal ball, helping to reconstruct events during pregnancy more accurately than ever before. A single drop of blood can yield DNA for genetic testing. Or, it may show signs of infection or metabolic disturbance. In California, newborns routinely have a few drops of blood taken from their heels and blotted onto filter paper to test for metabolic diseases. Already, several Program studies have used leftover blood spots, looking for genetic variants that may make an infant more susceptible to birth defects. We have recently launched a sample bank, expanding this idea even further. It takes advantage of another blood source—specimens from the Expanded AFP screening, a prenatal blood test, offered to California women in mid-pregnancy. Once outcome is known, we can test the blood to get clues about why some mothers had children with birth defects and others were protected.
Started in January 2003, the California Birth Defects Monitoring Program has over one million samples and as of May 2007 we will have stored blood from about 380,000 pregnant women. We will screen at least 100,000 women annually. Given recent technologic advances, each sample can be used for hundreds of tests. Biologic banking and testing are powerful new tools for finding causes of birth defects.