Discoveries and Data: Specific Conditions



To delineate birth defects associated with clefting, we looked at 4433 infants with oral clefts drawn from 2.5 million California births.

bullet-2645890 No other birth defects were seen in 73.5% of the children who had cleft lip with/without cleft palate and 47.5% of those with cleft palate alone.
bullet-2645890 Chromosome abnormalities were seen in 7.9% of those with cleft lip/palate and 9.8% with cleft palate alone. The most common chromosome diagnoses were trisomy 13 (31%), trisomy 18 (18%) and Down syndrome (5%).
bullet-2645890 4% of children had a sequence—a collection of birth defects all traceable to a single underlying abnormality. About 8% of those with cleft palate had the Robin sequence, where the tongue blocks palatal closure causing a U-shaped cleft. Midline clefts were common in the holoprosencephaly sequence.
bullet-2645890 6% of oral clefts were attributed to genetic disorders, in most cases, caused by autosomal dominant genes. Common conditions include Stickler syndrome, craniosynostosis syndromes and van der Woude syndrome (lip pits). 11% of cleft palate cases had identified genetic conditions, compared to only 2% of those with cleft lip with/without cleft palate.
bullet-2645890 There were only 9 cases attributed to known environmental causes—mostly fetal alcohol syndrome and fetal dilantin effects.
bullet-2645890 About 19% had multiple birth defects of unknown origin—about 15% of those with cleft lip/palate and 22% of those with cleft palate alone.


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