title: Genetic and environmental variance of renal parenchymal thickness: a twin study.
abstract: OBJECTIVE
  To estimate heritability and environmental effects on renal parenchymal thickness.
  
  
  METHODS
  In this twin study, renal parenchymal thickness of 98 Hungarian healthy adult twin pairs (68 monozygotic, 30 dizygotic) without kidney disease was measured bilaterally using renal ultrasound with Esaote MyLab 70X ultrasound machine with low-frequency curved transducers (1-8 MHz).
  
  
  RESULTS
  In both monozygotic and dizygotic group there were more women (76.5%). Mean right and left renal parenchymal thickness was 1.32±0.33 cm and 1.62±0.31 cm, respectively. Age- and sex-adjusted heritability of renal parenchymal thickness was 0.0% (95% confidence interval, 0.0 to 50.2%), shared and unshared environmental factor was 30.2% (4.1 to 55.9%) and 69.8% (45.8 to 89.5%), respectively.
  
  
  CONCLUSIONS
  This study shows a negligible role of heritability and an important role of environmental effects in developing renal parenchymal thickness, emphasizing the importance of lifestyle for primary prevention.
authors.affiliation: David Laszlo Tarnoki, Department of Radiology and Oncotherapy, Semmelweis University, 78/A Ulloi street, 1082 Budapest, Hungary, tarnoki4@gmail.com.
authors.forename: David Laszlo
authors.initials: DL
authors.lastname: Tarnoki
authors.forename: Adam Domonkos
authors.initials: AD
authors.lastname: Tarnoki
authors.forename: Levente
authors.initials: L
authors.lastname: Littvay
authors.forename: Pal
authors.initials: P
authors.lastname: Bata
authors.forename: Viktor
authors.initials: V
authors.lastname: Berczi
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Garami
authors.forename: Kinga
authors.initials: K
authors.lastname: Karlinger
mesh_terms: D000208:Acute Disease; D000328:Adult; D000367:Age Factors; D002908:Chronic Disease; D005260:Female; D059647:Gene-Environment Interaction; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D006801:Humans; D006814:Hungary; D007672:Kidney Cortex / Q000000981:diagnostic imaging / Q000473:pathology*; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000235:genetics* / Q000473:pathology*; D008019:Life Style; D008297:Male; D008875:Middle Aged; D011322:Primary Prevention; D012307:Risk Factors; D012737:Sex Factors; D014429:Twins, Dizygotic / Q000235:genetics; D014430:Twins, Monozygotic / Q000235:genetics; D014463:Ultrasonography