Craniofacial anomalies in twins.
Studies of twins provide insight into the relative contribution of genetic and environmental factors in the causality of structural anomalies. Thirty-five affected twin pairs were identified from a group of 1114 patients with congenital craniofacial deformities evaluated from 1972 to 1989. Forty-three of these 70 twins exhibited one or more craniofacial anomalies; these were analyzed for dysmorphic characteristics, zygosity, concordance, and family history. The anomalies were categorized into two groups: malformations and deformations. The malformations (n = 36) included hemifacial microsomia (n = 10), cleft lip and palate (n = 8), cleft palate (n = 4), rare facial cleft (n = 2), craniosynostosis (n = 2), Binder syndrome (n = 2), Treacher Collins syndrome (n = 2), craniopagus (n = 2), CHARGE association (n = 1), frontonasal dysplasia (n = 2), and constricted ears (n = 1). The deformations (n = 7) included plagiocephaly (n = 5), hemifacial hypoplasia (n = 1), and micrognathia (n = 1). Twenty-one monozygotic and 14 dizygotic twin pairs were identified. The concordance rate was 33 percent for monozygotic twins and 7 percent for dizygotic twins.(ABSTRACT TRUNCATED AT 250 WORDS)
Keusch
C F
CF
Harvard Medical School, Boston, Mass.
Mulliken
J B
JB
Kaplan
L C
LC
D000015:Abnormalities, Multiple / Q000209:etiology / Q000235:genetics*; D005147:Facial Bones / Q000002:abnormalities*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D011247:Pregnancy; D011248:Pregnancy Complications; D012886:Skull / Q000002:abnormalities*; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic