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Repeated measures of intraocular pressure result in higher heritability and greater power in genetic linkage studies.

Publication ,  Journal Article
Carbonaro, F; Andrew, T; Mackey, DA; Young, TL; Spector, TD; Hammond, CJ
Published in: Invest Ophthalmol Vis Sci
November 2009

PURPOSE: To analyze the effect of using one reading, the mean of two readings (from the same eye), or the mean of four readings (two from each eye) on the heritability estimates of intraocular pressure (IOP). This was a cohort study in which 344 pairs of twins, 163 monozygotic (MZ) and 181 dizygotic (DZ), were enrolled. METHODS: IOP was measured using three tonometers: the gold standard Goldmann applanation tonometer (GAT), the Ocular Response Analyzer (ORA; Reichert Buffalo, NY), and the Dynamic Contour Tonometer (DCT, Pascal; Swiss Microtechnology AG, Port, Switzerland). The main outcome measure was the heritability of IOP correlated with the number of measurements. RESULTS: The mean IOPs of all four readings with the three tonometers were: 14.1 +/- 2.9 mm Hg for GAT, 15.9 +/- 3.2 mm Hg for ORA, and 16.9 +/- 2.7 mm Hg for DCT. As the number of readings increased, the calculated heritability (h(2)) of IOP measured using the GAT readings increased from 0.56 for one reading (95% confidence interval [CI], 0.44-0.65) to 0.58 for the mean of two readings (95% CI, 0.46-0.67) to 0.64 for the mean of all four readings (two right and two left; 95% CI, 0.55-0.72). Similar results were seen with the other two instruments. CONCLUSIONS: The results demonstrated that the use of the mean of several readings from both eyes reduced measurement error, yielding a higher heritability estimate. The higher heritability would increase the power to detect linkage in a genome-wide analysis.

Duke Scholars

Published In

Invest Ophthalmol Vis Sci

DOI

EISSN

1552-5783

Publication Date

November 2009

Volume

50

Issue

11

Start / End Page

5115 / 5119

Location

United States

Related Subject Headings

  • Young Adult
  • Twins, Monozygotic
  • Twins, Dizygotic
  • Tonometry, Ocular
  • Quantitative Trait, Heritable
  • Ophthalmology & Optometry
  • Middle Aged
  • Male
  • Intraocular Pressure
  • Humans
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Carbonaro, F., Andrew, T., Mackey, D. A., Young, T. L., Spector, T. D., & Hammond, C. J. (2009). Repeated measures of intraocular pressure result in higher heritability and greater power in genetic linkage studies. Invest Ophthalmol Vis Sci, 50(11), 5115–5119. https://doi.org/10.1167/iovs.09-3577
Carbonaro, Francis, Toby Andrew, David A. Mackey, Terri L. Young, Tim D. Spector, and Christopher J. Hammond. “Repeated measures of intraocular pressure result in higher heritability and greater power in genetic linkage studies.Invest Ophthalmol Vis Sci 50, no. 11 (November 2009): 5115–19. https://doi.org/10.1167/iovs.09-3577.
Carbonaro F, Andrew T, Mackey DA, Young TL, Spector TD, Hammond CJ. Repeated measures of intraocular pressure result in higher heritability and greater power in genetic linkage studies. Invest Ophthalmol Vis Sci. 2009 Nov;50(11):5115–9.
Carbonaro, Francis, et al. “Repeated measures of intraocular pressure result in higher heritability and greater power in genetic linkage studies.Invest Ophthalmol Vis Sci, vol. 50, no. 11, Nov. 2009, pp. 5115–19. Pubmed, doi:10.1167/iovs.09-3577.
Carbonaro F, Andrew T, Mackey DA, Young TL, Spector TD, Hammond CJ. Repeated measures of intraocular pressure result in higher heritability and greater power in genetic linkage studies. Invest Ophthalmol Vis Sci. 2009 Nov;50(11):5115–5119.

Published In

Invest Ophthalmol Vis Sci

DOI

EISSN

1552-5783

Publication Date

November 2009

Volume

50

Issue

11

Start / End Page

5115 / 5119

Location

United States

Related Subject Headings

  • Young Adult
  • Twins, Monozygotic
  • Twins, Dizygotic
  • Tonometry, Ocular
  • Quantitative Trait, Heritable
  • Ophthalmology & Optometry
  • Middle Aged
  • Male
  • Intraocular Pressure
  • Humans