title: X chromosome parental origin and aortic stiffness in turner syndrome.
abstract: BACKGROUND
  Aortic abnormalities contribute to increased morbidity and mortality of women with Turner syndrome (TS). Impaired aortic stiffness may prove to have clinical prognostic value in TS as is the case in other diseases such as Marfan syndrome, diabetes and hypertension. Additionally, the parental origin of the X chromosome in TS may influence aortic stiffness.
  
  
  OBJECTIVE
  To assess the relation between X chromosome parental origin and aortic stiffness in TS patients.
  
  
  METHODS
  Twenty-four subjects with TS participated in this cross-sectional study at a tertiary care centre. The parental origin of the X chromosome was determined. Cardiac-gated multidetector computerized tomography (MDCT) was performed and distensibility of the ascending aorta (AA), a measure of aortic stiffness, was calculated.
  
  
  RESULTS
  Fourteen women were Xm (maternal origin) and 10 were Xp (paternal origin) for their inheritance of the single X chromosome. Age, body size, blood pressure and AA areas were similar in the two groups. However, the calculated AA distensibility was significantly lower in the Xm group (2·8 ± 1·1 mm/Hg) than in the Xp group (4·1 ± 1·5 mm/Hg); P < 0·05. Conclusion This study demonstrates that TS subjects that inherit their single X chromosome from their mother (Xm) have a significantly stiffer aorta compared with the TS with a paternally originating X chromosome (Xp), consistent with a potentially greater risk for cardiovascular complications. These findings suggest that parental chromosomal analysis and aortic stiffness measurements would be useful for the risk assessment and clinical management of TS patients.
authors.affiliation: Biomedical and Metabolic Imaging Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Khaled Z
authors.initials: KZ
authors.lastname: Abd-Elmoniem
authors.forename: Vladimir K
authors.initials: VK
authors.lastname: Bakalov
authors.forename: Jatin R
authors.initials: JR
authors.lastname: Matta
authors.forename: Nancy
authors.initials: N
authors.lastname: Muldoon
authors.forename: John A
authors.initials: JA
authors.lastname: Hanover
authors.forename: Carolyn A
authors.initials: CA
authors.lastname: Bondy
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Gharib
mesh_terms: D000328:Adult; D041321:Chromosomes, Human, X / Q000235:genetics*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D014424:Turner Syndrome / Q000235:genetics* / Q000503:physiopathology*; D059289:Vascular Stiffness / Q000235:genetics / Q000502:physiology