A gene that plays a critical role in the development of cleft palates and other skull malformations that compose the most common congenital birth defects in humans have been identified, according to an article in the September issue of the journal Development.
The transforming growth factor-beta, or TGF-ß, gene sends critical instructions to neural crest cells, which form the bony part of the palate. When such signals are not there, the palate does not form properly.
The disruption in the process occurs when the TGF-ß, gene produces a defective form of the protein needed for healthy craniofacial development, say researchers at the University of Southern California School of Dentistry, Los Angeles, and Vanderbilt University, Nashville.
"When you are missing this molecule in the palate itself, it disrupts the cell proliferation process," said Dr. Yang Chai, an associate professor of craniofacial sciences and therapeutics, USC School of Dentistry.
When researchers created a mutation in the TGF-ß, gene in mice, 100 percent of their 200 offspring were born with cleft palates similar to those found in humans.
"This clearly indicates that the gene is critical in controlling the palate development," said Dr. Chai.
The majority of cleft lips and palates are caused by a combination of genetic defect and environmental factors. "However," Dr. Chai said, "up to 30 percent of such defects are the strict result of gene formation.
"We could screen the family with a history of clefting," he continued. "If they carry the particular mutation, someday gene therapy might be able to help the embryos."
