Hyperbilirubinemia is an increased level of bilirubin in the blood. Bilirubin is a reddish-yellow fluid that results when hemoglobin, a protein in the blood, is broken down. As bilirubin increases in the body, it causes the skin to turn yellow (called jaundice).

Jaundice is common in newborn babies. Most jaundice seen in newborn babies is not serious and is due to immaturity of the body organs that get rid of bilirubin. However, some babies with very high levels of bilirubin in their body develop problems with their brain. In these cases, if the high bilirubin level is not recognized and treated early, the resulting damaging effects to these babies cannot be corrected.

Recent research suggests that better and early identification of babies that have high bilirubin levels can reduce the damaging effects. This study is designed to help us gain knowledge about gene differences in newborns with severe hyperbilirubinemia and hopefully better understand and manage these conditions in the future.