Melanocortin 1 receptor genotype, past environmental sun exposure, and risk of multiple sclerosis
Dwyer, T and van der Mei, IAF and Ponsonby, AL and Taylor, BV and Stankovich, J and McKay, JD and Thomson, RJ and Polanowski, AM and Dickinson, JL (2008) Melanocortin 1 receptor genotype, past environmental sun exposure, and risk of multiple sclerosis. Neurology, 71 (8). pp. 583-589. ISSN 0028-3878
|PDF - Full text restricted - Requires a PDF viewer|
Official URL: http://dx.doi.org/10.1212/01.wnl.0000323928.57408.93
Objective: Low past sun exposure, fair skin type, and polymorphisms of the MC1R gene have been associated with multiple sclerosis (MS) risk. We aimed to investigate the interplay between melanocortin 1 receptor gene variants, red hair/fair skin phenotype, and past environmental sun exposure in MS.
Methods: Population-based case–control study in Tasmania, Australia, involving 136 cases with MS and 272 controls randomly drawn from the community and matched on sex and year of birth. Measures included past sun exposure by calendar and questionnaire, spectrophotometric skin type, and MC1R genotype, with any MC1R Arg151Cys, Arg160Trp, or
Asp294His alleles present denoted as red hair color (RHC) variant.
Results: The association between RHC variant genotype and MS was more evident for women (odds ratio 2.02 [1.15–3.54]) than for men (odds ratio 0.65 [0.27–1.57]) (difference in effect, p 0.03). The RHC variant genotype was associated with behavioral sun avoidance. In addition, increasing summer sun exposure at ages 6 through 10 years was associated with reduced MS risk among those with no RHC variant (p 0.03), but not among those with RHC variant genotype (p 0.15; difference in effect, p 0.02). Similar findings were evident for other past sun exposure measures and when the sample was restricted to women only.
Conclusion: The interplay between red hair color variant genotype, red hair/fair skin phenotype, and multiple sclerosis (MS) is complex. The modification of past sun exposure by MC1R genotype provides further support that ultraviolet radiation or derivatives such as vitamin D may be causally related to a reduced MS risk.
Copyright © 2008 by AAN Enterprises, Inc. |
|Deposited By:||Ms Emma Stubbs|
|Deposited On:||23 Sep 2008 14:55|
|Last Modified:||06 Mar 2009 12:14|
|ePrint Statistics:||View statistics for this ePrint|
Repository Staff Only: item control page