Infants with cleft lip/cleft palate.

Abstract

A cleft of the lip and/or palate occurs approximately once in 750 live births with some variability among various racial groups. As an isolated defect, cleft lip with or without cleft palate is etiologically distinct from cleft palate alone. More than 250 clefting syndromes, most of them relatively uncommon, have been described. In 1970, less than 3% of all cases of cleft lip and/or palate were thought to be associated with identifiable syndromes. A recent survey from a major cleft palate center in New York showed that 30% of patients had recognizable conditions. Some of these included genetic syndromes and others like the charge association or those related to environmental agents were sporadic. Another 30% of cases had one or more associated anomalies, although a specific syndromic diagnosis or etiologic basis could not be identified. The remaining 40% had isolated clefts. A summary of syndromes with cleft lip and palate by etiology is given in Table 1. Approximately, half of the recognized syndromes are due to single-gene disorders with an equal distribution among autosomal dominant and autosomal recessive inheritance. Chromosomal abnormalities account for 18% of the clefting syndromes and would invariably be associated with other malformations, delayed development, and poor prognosis.