Background Hypovitaminosis D is prevalent worldwide. It is more prevalent in Eastern Asia region, including Korea. In addition to various environmental factors that influence serum 25-hydroxyvitamin D (25(OH)D) concentration, genetic influence also plays a significant role based on studies estimating the heritability of 25(OH)D in non-Asian populations. The objective of this study was to determine the genetic influence on serum 25(OH)D concentration in Korean men using the twin and family data. Methods A total of 1126 Korean male adult twins and family members from the Healthy Twin Study with serum 25(OH)D measurement were included in this cross-sectional study. Intraclass correlation coefficients (ICCs) and heritability were calculated by mixed linear regression analysis and quantitative genetic analysis after adjusting for environmental and lifestyle factors. Results Mean (± standard deviation; SD) of serum 25(OH)D concentration was 15.34 ± 6.18 ng/ml. The prevalence of vitamin D insufficiency was 19.8% and that of vitamin D deficiency was 77.9%. After adjusting for age, the highest ICC (0.61) was observed for monozygotic twin pairs while the lowest ICC (0.31) was found for father-son pairs. Age-adjusted heritability was estimated to be 58%. When physical activity, multivitamin intake and season of blood sampling were further considered, the ICC and heritability did not materially change. In the sensitivity analysis after excluding known multivitamin users, age-adjusted heritability was reduced to 44%. Conclusions In our study of Korean male twins and family members, heritability of 25(OH)D was moderately high. This supports the finding that genetic factors have significant influence on vitamin D status.

中文翻译：

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遗传对韩国男性血清 25-羟基维生素 D 浓度的影响：一项横断面研究。

背景维生素D缺乏症在世界范围内普遍存在。它在包括韩国在内的东亚地区更为普遍。除了影响血清 25-羟基维生素 D (25(OH)D) 浓度的各种环境因素外，根据估计 25(OH)D 在非亚洲人群中的遗传力的研究，遗传影响也起着重要作用。本研究的目的是利用双胞胎和家庭数据确定遗传对韩国男性血清 25(OH)D 浓度的影响。方法 在这项横断面研究中，共有 1126 名来自健康双胞胎研究的韩国成年男性双胞胎及其家庭成员进行了血清 25(OH)D 测量。在调整环境和生活方式因素后，通过混合线性回归分析和定量遗传分析计算组内相关系数（ICCs）和遗传力。结果血清25(OH)D浓度的平均值（±标准差；SD）为15.34±6.18 ng/ml。维生素D不足的患病率为19.8%，维生素D缺乏的患病率为77.9%。调整年龄后，单卵双胞胎的 ICC 最高（0.61），而父子对的 ICC 最低（0.31）。年龄调整后的遗传力估计为 58%。当进一步考虑体力活动、多种维生素摄入量和采血季节时，ICC 和遗传力没有实质性变化。在排除已知的多种维生素使用者后的敏感性分析中，年龄调整后的遗传力降低到 44%。结论 在我们对韩国男性双胞胎和家庭成员的研究中，25(OH)D 的遗传力中等偏高。这支持了遗传因素对维生素 D 状态有显着影响的发现。