Genetics of Cleft Lip and Palate – Is it still patchy?

Clefts of the lip and/or palate (CL/P) are immediately recognizable disruptions of normal facial structure. Approximately 1 in 700 children born have a cleft lip or a cleft palate or both with a lifetime cost of treatment estimated at $200,000. CLP and CP individuals may experience difficulties in feeding, speaking, hearing and social integration. Recent successes in genome-wide linkage and association studies have identified novel loci that are significantly associated with CLP. In larger cohorts of people with CL/P, approximately 20% have other relatives with CL/P, and an increased prevalence is observed among first and second degree relatives. Many syndromes with phenotypes that include CL/P are now known. In some of the CL/P syndromes, the genes involved have been identified and the list is constantly increasing, primarily due to improved sequencing facilities. Genetics of NSCLP has been investigated by various studies such as Familial and Segregational Analysis, Twin Studies, Linkage Analysis, Association studies. There is overlapping of genes determining syndromic and non¬syndromic forms of CL /P. Greater efforts are necessary in order to have a complete picture of the main factors involved in lip and palate malformation.