Cleft palate: players, pathways, and pursuits

Abstract

Cleft lip and palate is a common human birth defect, and its causes are being dissected through studies of human populations and through the use of animal models.Mouse models in particular have made a substantial contribution to our understanding of the gene pathways involved in palate development and the nature of signaling molecules that act in a tissue-specific manner at critical stages of embryogenesis (see the related article beginning on page 1692).Related work has provided further support for investigating the role of common environmental triggers as causal covariates.Human birth defects arise from many etiologies, including single-gene disorders, chromosome aberrations, exposure to teratogens, and sporadic conditions of unknown cause.Birth defect syndromes include multiple structural abnormalities and/or cognitive delays.However, most human birth defects affect a single organ system, and those disrupting facial structures are found in approximately 1% (or 1 million) of infants born worldwide each year.The most common of these birth defects is cleft lip and/or palate, a complex trait caused by multiple genetic and environmental factors (1).