Duggirala R, González Villalpando C, O'Leary D H, Stern M P, Blangero J
Department of Medicine, University of Texas Health Science Center at San Antonio, TX 78284-7873, USA.
Stroke. 1996 May;27(5):833-7. doi: 10.1161/01.str.27.5.833.
Other than the documented associations of risk factors and carotid artery wall thickness, the genetic basis of variation in carotid artery intimal-medial thickness (IMT) is unknown. The purpose of this study was to examine the extent to which variation in common carotid artery (CCA) IMT and internal carotid artery (ICA) IMT are under genetic control.
The sibship data used for this analysis were part of an epidemiological survey in Mexico City. The CCA and ICA analyses were based on 46 and 44 sibships of various sizes, respectively. The CCA and ICA IMTs were measured with carotid ultrasonography. Using a robust variance decomposition method, we performed genetic analyses of CCA IMT and ICA IMT measurements with models incorporating several cardiovascular risk factors (eg, lipids, diabetes, blood pressure, and smoking) as covariates.
After accounting for the effects of covariates, we detected high heritabilities for CCA IMT (h2 = 0.92 +/- 0.05, P = .001) and ICA IMT (h2 = 0.86 +/- 0.13, P = .029). Genes accounted for 66.0% of the total variation in CCA IMT, whereas 27.7% of variation was attributable to covariates. For ICA IMT, genes explained a high proportion (74.9%) of total phenotypic variation. The covariates accounted for 11.5% of variation in ICA IMT.
Our results suggest that substantial proportions of phenotypic variance in CCA IMT and ICA IMT are attributable to shared genetic factors.
除了已记录的危险因素与颈动脉壁厚度之间的关联外，颈动脉内膜中层厚度（IMT）变化的遗传基础尚不清楚。本研究的目的是探讨颈总动脉（CCA）IMT和颈内动脉（ICA）IMT的变化在多大程度上受基因控制。
用于本次分析的同胞数据是墨西哥城一项流行病学调查的一部分。CCA和ICA分析分别基于46个和44个不同大小的同胞对。通过颈动脉超声测量CCA和ICA的IMT。使用稳健的方差分解方法，我们对CCA IMT和ICA IMT测量值进行了遗传分析，模型纳入了几种心血管危险因素（如血脂、糖尿病、血压和吸烟）作为协变量。
在考虑协变量的影响后，我们检测到CCA IMT（h2 = 0.92 +/- 0.05，P = .001）和ICA IMT（h2 = 0.86 +/- 0.13，P = .029）具有较高的遗传力。基因占CCA IMT总变异的66.0%，而27.7%的变异归因于协变量。对于ICA IMT，基因解释了总表型变异的很大比例（74.9%）。协变量占ICA IMT变异的11.5%。
我们的结果表明，CCA IMT和ICA IMT表型变异的很大一部分归因于共同的遗传因素。
