Investigative ophthalmology & visual science · 2008
A canine model of inherited myopia: familial aggregation of refractive error in labrador retrievers.
Сравнительное исследованиеСтатьяПоддержка исследования: вне правительства СШАНазвание и аннотация: Перевод пока не подготовлен
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Black Joanna, Browning Sharon R, Collins Andrew V, Phillips John R
Аннотация
PURPOSE: To determine whether the distribution of naturally occurring myopia in Labrador Retrievers has a genetic component.
METHODS: Pedigree records of a large canine family were analyzed. Pure Labrador Retrievers, 1 to 8 years of age, free of ocular disease, and available for testing were studied. Refractive error was measured by cycloplegic retinoscopy in both eyes. The family included mating loops, and so an expectation maximization (EM) algorithm (multivar program, MORGAN software; University of Washington, Seattle) was used to calculate log likelihoods of refractive error with environmental and additive genetic models. The fixed effects of coat color, sex, and litter size were also tested.
RESULTS: In our sample of 116 dogs from this one family, the average spherical equivalent refraction (SER) was -0.41 D (range, -5.38 to +1.65 D, mean of both eyes, n = 116): 31% were myopic (SER <or= -0.50 D), 60% were emmetropic (SER = -0.49 to +0.99 D), and 9% were hyperopic (SER >or= +1.00 D). The significance of fixed and genetic effects was tested by comparing the full model (including genetic and all fixed effects) to models with one effect removed. Litter size and additive genetic effects were significant (P = 0.0013 and P = 0.000093, respectively), whereas sex and coat color were not. The overall variance in SER was accounted for approximately equally by additive genetic variance and residual/environmental variance. Narrow sense heritability of SER was 0.506.
CONCLUSIONS: The distribution of refractive error within this family of Labrador Retrievers had a significant genetic component, but was also influenced by other factors (litter size, and undefined residual/environmental effects). The dog represents a unique model for the study of naturally occurring, heritable, high-prevalence, low-degree myopia.
METHODS: Pedigree records of a large canine family were analyzed. Pure Labrador Retrievers, 1 to 8 years of age, free of ocular disease, and available for testing were studied. Refractive error was measured by cycloplegic retinoscopy in both eyes. The family included mating loops, and so an expectation maximization (EM) algorithm (multivar program, MORGAN software; University of Washington, Seattle) was used to calculate log likelihoods of refractive error with environmental and additive genetic models. The fixed effects of coat color, sex, and litter size were also tested.
RESULTS: In our sample of 116 dogs from this one family, the average spherical equivalent refraction (SER) was -0.41 D (range, -5.38 to +1.65 D, mean of both eyes, n = 116): 31% were myopic (SER <or= -0.50 D), 60% were emmetropic (SER = -0.49 to +0.99 D), and 9% were hyperopic (SER >or= +1.00 D). The significance of fixed and genetic effects was tested by comparing the full model (including genetic and all fixed effects) to models with one effect removed. Litter size and additive genetic effects were significant (P = 0.0013 and P = 0.000093, respectively), whereas sex and coat color were not. The overall variance in SER was accounted for approximately equally by additive genetic variance and residual/environmental variance. Narrow sense heritability of SER was 0.506.
CONCLUSIONS: The distribution of refractive error within this family of Labrador Retrievers had a significant genetic component, but was also influenced by other factors (litter size, and undefined residual/environmental effects). The dog represents a unique model for the study of naturally occurring, heritable, high-prevalence, low-degree myopia.