title: Heritability of venous biomechanics.
abstract: OBJECTIVE
  Altered venous biomechanics may contribute to the pathogenesis of venous diseases, and their heritability is less known.
  
  
  RESULTS
  Seventy-eight monozygotic twin pairs (aged 42.4 ± 16.8 years) and 24 same-sex dizygotic twin pairs (aged 50.5 ± 16.1 years) were examined. Anteroposterior and mediolateral diameters of the common femoral vein were measured by ultrasonography. Measurements were made both in supine and in standing body positions, with or without controlled forced expiration (Valsalva test). High correlation of diameter, capacity, and distensibility values was found between twin pairs. The univariate heritability (A), shared (C), and unshared (E) environmental effects model has shown 39.3% genetic component of the variance of low pressure, 37.9% of high-pressure venous capacity, and 36.4% of maximal capacity changes, even after elimination of sex, age, and body weight effects. Bivariate Cholesky analysis revealed substantial covariance of inherited body weight and venous capacity components (57.0%-81.4%).
  
  
  CONCLUSIONS
  Femoral vein capacity and elasticity depend ≈30% to 40% on genetic factors, and this value in the standing body position can reach 50%. A relatively high genetic covariance was found between weight and femoral vein capacity and elasticity. Our work might yield some new insights into the inheritance of venous diseases that are associated with altered venous biomechanics and help elucidate the involved genes.
authors.affiliation: Research Group for Inflammation Biology and Immunogenomics of Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary. molnandi@gmail.com
authors.forename: Andrea Àgnes
authors.initials: AÀ
authors.lastname: Molnár
authors.forename: Adám Domonkos
authors.initials: AD
authors.lastname: Tárnoki
authors.forename: Dávid László
authors.initials: DL
authors.lastname: Tárnoki
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Kulcsár
authors.forename: Levente
authors.initials: L
authors.lastname: Littvay
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Garami
authors.forename: István
authors.initials: I
authors.lastname: Préda
authors.forename: Róbert Gábor
authors.initials: RG
authors.lastname: Kiss
authors.forename: Viktor
authors.initials: V
authors.lastname: Bérczi
authors.forename: Agnes
authors.initials: A
authors.lastname: Lannert
authors.forename: Emil
authors.initials: E
authors.lastname: Monos
authors.forename: György László
authors.initials: GL
authors.lastname: Nádasy
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D004200:Diseases in Twins / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D004548:Elasticity; D004777:Environment; D005260:Female; D005268:Femoral Vein / Q000000981:diagnostic imaging / Q000503:physiopathology*; D020022:Genetic Predisposition to Disease; D006439:Hemodynamics / Q000235:genetics*; D040941:Heredity; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D018570:Risk Assessment; D012307:Risk Factors; D016683:Supine Position; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*; D014463:Ultrasonography; D014652:Vascular Diseases / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D059289:Vascular Stiffness / Q000235:genetics; D014690:Venous Pressure / Q000235:genetics