title: Genetic analysis of dental traits in 82 pairs of female-female twins.
abstract: OBJECTIVE
  To study systematically the heritability of dental traits.
  
  
  METHODS
  Eighty-two pairs of female-female twins from 6 to 12 years old were collected. Twin zygosity diagnosis was made by DNA fingerprinting. The study was composed of questionnaires, oral examinations, model measurements, and panoramic radiographs. The same analytic method was used for each of the dental traits and comparison of their heritability was made.
  
  
  CONCLUSIONS
  According to the significance of difference and the level of heritability, the dental traits were divided into four types: strong, median, weak, and weaker heritability. The number of third molars present, tooth size, arch size, and upper lateral incisor malformation were under strong genetic influence; hypodontia indicated a median heritability; a weak heritability was seen in tooth eruption and caries, and a weaker heritability was found in occlusal traits. The division made it easy to learn the genetic characteristics of dental traits systematically and supplemented the theory of dental genetics.
authors.affiliation: Department of Pediatric Dentistry, School of Stomatology, Beijing Medical University (BMU), P. R. China.
authors.forename: H
authors.initials: H
authors.lastname: Liu
authors.forename: H
authors.initials: H
authors.lastname: Deng
authors.forename: C F
authors.initials: CF
authors.lastname: Cao
authors.forename: H
authors.initials: H
authors.lastname: Ono
mesh_terms: D000848:Anodontia / Q000235:genetics; D002648:Child; D016172:DNA Fingerprinting; D003724:Dental Arch / Q000033:anatomy & histology; D003731:Dental Caries / Q000235:genetics; D003766:Dental Occlusion; D003817:Dentition; D004200:Diseases in Twins / Q000235:genetics; D005260:Female; D006801:Humans; D007180:Incisor / Q000002:abnormalities; D008310:Malocclusion / Q000235:genetics; D009811:Odontometry; D014071:Tooth Abnormalities / Q000235:genetics*; D014078:Tooth Eruption / Q000235:genetics*