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Normal facial development enables individuals to perform critical auditory, visual, breathing, masticatory, expressive, and vocal functions. Facial primordia appears near the mouth's future site in the 4th week of development. Henceforth, facial development becomes a complex process involving the formation of various primordial tissues. Many congenital facial anomalies have genetic causes, though some arise from preventable teratogen exposures. Developmental facial abnormalities can be disfiguring and devastating. The treatment of congenital facial disorders is often delayed until after birth because they are well-tolerated in utero.[1]

Facial developmental anomalies may be due to genetic or environmental causes. Pregnancy-related etiologies include fetal alcohol syndrome, uterine growth restriction, oligohydramnios, and maternal infections.[5] Genetic conditions that can cause abnormal facial development include Pierre-Robin, Treacher-Collins, Fragile X, Down, and DiGeorge syndromes.[6][7] An orofacial cleft may likewise be due to genetics, environmental factors, or both. This condition is known to run in families. Several genes are implicated, including the cleft lip and palate transmembrane protein 1 (CLPTM1), poliovirus receptor-related 1 (PVRL1), and γ-aminobutyric acid receptor subunit β-3 (GABRB3) genes.[8][9] Cleft palates may occur as part of genetic conditions like Treacher-Collins, Stickler, and Loeys-Dietz syndromes.[10][11] Environmental factors found to cause palatal clefts include fetal hypoxia from maternal smoking, alcohol abuse, maternal anticonvulsant therapy, and retinoid intake. Holoprosencephaly (HPE) occurs due to failed cerebral hemisphere separation and is associated with forebrain and facial midline defects.[12] The condition may result from SHH signaling dysfunction or altered bone morphogenic proteins (BMPs).