Messenger - Vol. 2, No. 3, Page 9 Summer 1993 On Research Midget monitors record heart dysfunction in chick embryos By conducting research on embryonic distress in chickens, Harold White may provide insight into Sudden Infant Death Syndrome (SIDS) among humans. The professor of chemistry and biochemistry studies fertilized eggs that lack riboflavin, or Vitamin B2, because of a genetic defect in the hens that lay them. Without this essential vitamin, the chicken embryos die approximately 13 days after fertilization, instead of hatching in the usual 21 days. For his research, he must monitor the embryos, study the onset and progress of heart dysfunction and determine precisely the time of death. "The heartbeat of a chick embryo is so difficult to detect that a heart monitor that amplifies the sound a half million times must be attached to the egg to record it," White says. The heart monitor, or miniature microphone, feeds information into a computer. White currently has one monitor, and a recent American Heart Association grant will enable him to design and build 16 monitors to study the hearts of several embryos simultaneously. The computer analysis of an embryo heart resembles a miniature EKG, showing a sharp dip when the heart ceases to function and the embryo dies. By comparing these print-outs, White looks for consistent signs of the onset of embryonic distress. He also compares these riboflavin-deficient eggs with viable eggs from the same flock that have received riboflavin injections. "The heart is a muscle that requires oxygen to function," White says. "If there is no riboflavin, an inability to use oxygen occurs and the heart stops." While no SIDS deaths have been linked to riboflavin deficiency, there are some metabolic similarities between the rapidly developing chicken embryo and infants at the age when most SIDS deaths occur, White says. White's development of more sophisticated heart monitors for his riboflavin research may also have an impact on other research areas that use a heart monitor. "Sydney Brenner, the Nobel Prize-winning molecular biologist, once said, 'Progress in science depends on new techniques, new discoveries and new ideas, probably in that order,'" White says. -Sue Swyers Moncure