Association of common SIX6 polymorphisms with peripapillary retinal nerve fiber layer thickness: the Singapore Chinese Eye Study.

Journal Article (Journal Article)

PURPOSE: Recently the common SIX6 missense variant rs33912345 was found to be highly associated with glaucoma. The aim of this study was to investigate the association between this SIX6 variant and peripapillary retinal nerve fiber layer (RNFL) thickness measured by spectral-domain optical coherence tomography (SD-OCT) in a population setting. METHODS: Study subjects were enrolled from the Singapore Chinese Eye Study (SCES), a population-based survey of Singaporean Chinese aged 40 years or older. Subjects underwent a comprehensive ocular examination. Spectral-domain OCT was used to measure RNFL thicknesses. Genotyping of SIX6 rs33912345 (Asn141His) was performed using HumanExome BeadChip. RESULTS: A total of 2129 eyes from 1243 SCES subjects (mean age: 55.0 ± 7.4 years) with rs33912345 genotype data and SD-OCT images were included for the analysis. Of these, 26 eyes of 21 subjects had glaucoma. The frequency of rs33912345 risk variant C (His141) was 80% in the study subjects. Each rs33912345 C allele was associated with a decrease of 1.44 μm in RNFL thickness after adjusting for age, sex, genetic principal components, and axial length (P = 0.001). These associations remained similar in 2096 nonglaucoma eyes in which each C allele was associated with a decrease of 1.39 μm in RNFL thickness (P = 0.001). The strongest association was observed in the superior RNFL sector (a decrease of 2.83 μm per risk allele, P < 0.001) followed by the inferior RNFL sector (a decrease of 2.24 μm per risk allele, P = 0.003), while the association did not reach significance in the nasal and temporal sectors. CONCLUSIONS: Nonglaucomatous individuals with the SIX6 missense variant have reduced RNFL thickness in regions known to be particularly affected in those with glaucoma. This may be the primary mechanism for increased risk of POAG in individuals who carry the SIX6 His141 risk variant.

Full Text

Duke Authors

Cited Authors

  • Cheng, C-Y; Allingham, RR; Aung, T; Tham, Y-C; Hauser, MA; Vithana, EN; Khor, CC; Wong, TY

Published Date

  • December 23, 2014

Published In

Volume / Issue

  • 56 / 1

Start / End Page

  • 478 - 483

PubMed ID

  • 25537207

Pubmed Central ID

  • PMC4544593

Electronic International Standard Serial Number (EISSN)

  • 1552-5783

Digital Object Identifier (DOI)

  • 10.1167/iovs.14-15863


  • eng

Conference Location

  • United States