REMINISCENCING THE GENETICS OF OROFACIAL CLEFTING

Cleft lip with or without cleft palate is the most common craniofacial birth defect (1/1000 live births), caused by a complex interaction of chromosome rearrangements, gene mutations as well as environmental influences. The frequent occurrence of orofacial clefting, along with their extensive psychological, surgical, speech and dental involvement emphasize the importance of identifying the underlying etiology. Rare cleft forms, where they occur as a component of multiple congenital anomaly syndromes, have Mendelian or Teratogenic origins; the non-syndromic forms of orofacial clefts are more common and are probably due to secondary gene-environment interactions. The purpose of our review is to provide a short summary of the vast spectrum of genetic architecture of orofacial clefting covering both syndromic as well as nonsyndromic forms of clefting .Although the gene identification process for orofacial clefting in humans is in an early stage (especially in India); the research pace is rapidly accelerating worldwide. Ongoing human genome wide linkage studies have identified regions that are likely to contain genes that when mutated cause orofacial clefting .Our main aim is to bring together a discussion of new and previously identified candidate genes to create a more cohesive picture of interacting pathways that shape the human craniofacial region. In addition, sequencing of protein coding regions in candidate genes and screening for genetic variation in noncoding regulatory elements, will help in the area of advanced research. Furthermore, statistical geneticists are developing new methods to characterize both gene-gene and gene-environment inter-actions, for explaining the pathology of this common birth defect. The ultimate goal of these studies is to provide knowledge for more accurate risk counseling and the development of preventive therapies. Though India has an estimated population of one million untreated cleft patients, facilities for its treatment have been limited and are not evenly distributed across the country. Paucity of committed cleft surgeons, poverty, illiteracy, superstitions, poor connectivity in some remote areas; severely limit the chances of an average cleft lip Indian child from receiving rational and effective treatment for his malady. The Oscar winning documentary film “Smile Pinki” highlighted the plight of cleft patients in our country. The film stood testimony to the passion of dedicated doctors, social workers and paramedical staffs toiling in the Indian heartland as they treated unfortunate cleft children with the support of the “Smile Train Project”.