Heritability of mandibular cephalometric variables in twins with completed craniofacial growth.
To determine genetic and environmental impact on mandibular morphology using lateral cephalometric analysis of twins with completed mandibular growth and deoxyribonucleic acid (DNA) based zygosity determination.



The 39 cephalometric variables of 141 same gender adult pair of twins were analysed. Zygosity was determined using 15 specific DNA markers and cervical vertebral maturation method was used to assess completion of the mandibular growth. A genetic analysis was performed using maximum likelihood genetic structural equation modelling (GSEM).



The genetic heritability estimates of angular variables describing horizontal mandibular position in relationship to cranial base and maxilla were considerably higher than in those describing vertical position. The mandibular skeletal cephalometric variables also showed high heritability estimates with angular measurements being considerably higher than linear ones. Results of this study indicate that the angular measurements representing mandibular skeletal morphology (mandibular form) have greater genetic determination than the linear measurements (mandibular size).



The shape and sagittal position of the mandible is under stronger genetic control, than is its size and vertical relationship to cranial base.
*Clinic of Orthodontics, Medical Academy, m.sidlauskas@gmail.com.
Mantas
M
Šidlauskas
**Institute of Biology Systems and Genetics, Veterinary Academy and.
Loreta
L
Šalomskienė
**Institute of Biology Systems and Genetics, Veterinary Academy and.
Irena
I
Andriuškevičiūtė
*Clinic of Orthodontics, Medical Academy.
Monika
M
Šidlauskienė
*Clinic of Orthodontics, Medical Academy.
Žygimantas
Ž
Labanauskas
*Clinic of Orthodontics, Medical Academy.
Arūnas
A
Vasiliauskas
***Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania.
Limas
L
Kupčinskas
***Institute for Digestive Research, Lithuanian University of Health Sciences, Kaunas, Lithuania.
Simonas
S
Juzėnas
*Clinic of Orthodontics, Medical Academy.
Antanas
A
Šidlauskas
D000293:Adolescent; D000328:Adult; D002508:Cephalometry / Q000379:methods; D002574:Cervical Vertebrae / Q000254:growth & development; D005147:Facial Bones / Q000254:growth & development; D005260:Female; D059647:Gene-Environment Interaction; D005819:Genetic Markers; D006801:Humans; D008297:Male; D008334:Mandible / Q000033:anatomy & histology / Q000254:growth & development*; D008437:Maxilla / Q000033:anatomy & histology / Q000254:growth & development; D019655:Quantitative Trait, Heritable; D019291:Skull Base / Q000033:anatomy & histology / Q000254:growth & development; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*; D055815:Young Adult
D005819:Genetic Markers