Scientists at the University of Illinois are reported to have discovered what makes breast milk far superior than infant formula for a child.

"For the first time, we can see that breast milk induces genetic pathways that are quite different from those in formula-fed infants," quoted, Sharon Donovan, a U of I professor of nutrition.

In addition, she said that despite of the fact that formula makers have attempted to develop a product that's as much similar to breast milk, the study succeeded to discern that hundreds of genes were expressed in a different manner in the breast-fed and formula-fed groups.

"The intestinal tract of the newborn undergoes marked changes in response to feeding. And the response to human milk exceeds that of formula, suggesting that the bioactive components in breast milk are important in this response," she added.

However, the scientists are in a bid to design a signature gene or group of genes to use as a biomarker for breast-fed infants.

The study is reported to adopt a new technique to observing the intestinal gene expression in 22 healthy infants-12 breast-fed, 10 formula-fed.

The study is posted to publish in the June 2010 issue of the American Journal of Physiology, Gastrointestinal and Liver Physiology.