Cleft lip with or without cleft palate (CL/P) is one of the most common birth defects, but its etiology is largely unknown. It is very likely that both genetic and environmental factors contribute to this malformation.

Classification

 Sporadic cleft lip - non-syndromic cleft lip
 Syndromic cleft lip

• Cleft lip/palate-ectodermal dysplasia syndrome (CLPED1) (MIM.225000)
• Margarita Island ectodermal dysplasia (MIM.225060)

Etiology

 Sporadic cleft lip - non-syndromic cleft lip

• germline mutations in PVRL1 gene (MIM.600644)
• genetic polymorphisms at the IRF6 locus are associated with nonsyndromic CL/P, with stronger association in Asian and South American populations.
• germline mutations in MSX1 gene (MIM.600644)

 Syndromic cleft lip

• cleft lip/palate-ectodermal dysplasia syndrome (CLPED1) (MIM.225000)
• germline mutations in PVRL1 gene (MIM.142983)

See also

 IRF6
 Van der Woude syndrome

References

 Jugessur A, Murray JC. Orofacial clefting: recent insights into a complex trait. Curr Opin Genet Dev. 2005 Jun;15(3):270-8. PMID: #15917202#