A group of researchers from the Institute of Human Genetics of the University of Bonn (Germany), led by Elisabeth Mangold, has managed to identify two common genetic variants associated with the harelip non-syndromic, which occurs with or without a split palate.

During the study, whose results have been published in the journal "Nature Genetics", we have analyzed the cases of 401 children affected by this malformation, comparing them with a control group composed of 1,323 healthy children, all of European origin.

Researchers have discovered that there are two genetic variants, on chromosome 17q22 and chromosome 10q25, that are associated with an increased risk of presenting this malformation, an anomaly that affects the structures that form the mouth, and that appears in one of every 700 births.

Thanks to previous studies, four locations are known at the genome level, which make individuals susceptible to malformation, and which show that genetic factors are more relevant than previously thought.

What is cleft lip

It is one of the most common congenital defects along with the cleft palate. In the cleft lip, at the beginning of pregnancy, the tissues that make up the mouth and face do not fuse normally, and as a result, a gap appears between the lips, the jaw, and occasionally the palate. An abnormality known as a cleft palate may also appear, which is an opening in the interior of the nasal cavity, which can compromise any part of the palate.

The sum of environmental factors, such as nutritional deficiencies or obesity of the infant, and genetic, are indicated as the main responsible for this alteration in the lips.

The treatment is surgical and is carried out in the first months after birth, although usually the patient needs reinterventions throughout life.

"Multifactorial Inheritance" by Bruce Korf for OPENPediatrics (November 2019).