Department of Medical Biochemistry, St. Olavs Hospital HF, Trondheim, Norway.
Scand J Clin Lab Invest. 2010 Apr;70(2):92-7. doi: 10.3109/00365510903527838.
Hereditary hemochromatosis (HH) is a genetic condition characterized by increased iron absorption. Most HH cases are homozygous for the C282Y mutation in the HFE gene, but accurate prevalence data for the Norwegian population is lacking. In population studies, serum transferrin saturation (TS) is commonly used as a screening test. However, the sensitivity and specificity of TS in this setting is not well documented. The purpose of this study was to determine the prevalence of the C282Y mutation in the general population, and to evaluate the diagnostic accuracy of the TS test as a screening criterion for finding C282Y homozygotes.
The hemochromatosis screening study in Nord-Trøndelag county, Norway (the HUNT2 study) comprised 65,238 participants. The HUNT biobank contains biological material and data from the participants, and 5000 individuals were randomly selected. Genotyping of the common HFE gene mutations was successful for 4827 samples, from which TS data existed for 4804 individuals. From these data we calculated the population frequency of the C282Y mutation, and the sensitivity and specificity of TS measurements.
The prevalence of C282Y homozygosity in the population was 0.75%. Using 55% (men) and 50% (women) as decision limits, the sensitivity of two consecutive elevated TS measurements was 90.0% for men and 55.0% for women, whereas the specificity was 99.6% and 99.4%, respectively.
An unbiased estimate of the C282Y homozygote prevalence in Norway is 0.75%. Two measurements of TS is an accurate screening test for C282Y homozygosity in men, but not in women.
遗传性血色素沉着症（HH）是一种以铁吸收增加为特征的遗传疾病。大多数 HH 病例是 HFE 基因 C282Y 突变的纯合子，但缺乏挪威人群的确切流行数据。在人群研究中，血清转铁蛋白饱和度（TS）通常用作筛查试验。然而，TS 在这种情况下的敏感性和特异性尚未得到很好的记录。本研究的目的是确定普通人群中 C282Y 突变的流行率，并评估 TS 试验作为发现 C282Y 纯合子的筛查标准的诊断准确性。
挪威特隆赫姆郡（HUNT2 研究）的血色病筛查研究共纳入 65238 名参与者。HUNT 生物库包含参与者的生物材料和数据，随机选择了 5000 人。对常见 HFE 基因突变进行基因分型，成功对 4827 个样本进行了基因分型，其中 4804 个个体存在 TS 数据。根据这些数据，我们计算了人群中 C282Y 突变的频率，以及 TS 测量的敏感性和特异性。
人群中 C282Y 纯合子的患病率为 0.75%。使用 55%（男性）和 50%（女性）作为决策限，两次连续升高的 TS 测量的敏感性分别为男性 90.0%和女性 55.0%，特异性分别为 99.6%和 99.4%。
挪威 C282Y 纯合子患病率的无偏估计值为 0.75%。两次 TS 测量是男性 C282Y 纯合子的准确筛查试验，但对女性则不然。
