The study by researchers from Karolinska Institutet in Sweden can lead the way to improved genetic diagnostic of individuals and families with orofacial clefts.
Cleft lip and palate is one of the most common birth defects and can be found in the form of cleft lip or cleft palate alone; or cleft lip and palate together.
Now, through an international collaboration between researchers from Sweden, USA, Finland and Israel, a second gene related to VWS has been found.
The researchers started by doing a so called genetic linkage study of a large family from Finland. The family had been diagnosed with VWS, albeit no IRF6 mutations had been found.
By comparing the DNA of affected individuals with DNA from healthy family members, the researchers identified another gene, called Grainy-head like 3 (GRHL3), which was mutated only in the affected family members.
The same gene was found to be altered in 7 additional families with VWS where no IRF6 mutations had been found previously.
"The discovery of a new gene, GRHL3, responsible for the most common of the syndromic forms of cleft lip and palate means that researcher or clinicians with collections of families or isolated cases with cleft lip and palate, syndromic or non-syndromic, now will be able to look for mutations in this gene," lead researcher Myriam Peyrard-Janvid said.
"As it has been shown for IRF6, one or several polymorphisms in GRHL3 might be found to be associated with increased risk of clefts in non-syndromic cases," Peyrard-Janvid added.
The study is published in the American Journal of Human.