Kasvosve Ishmael, Gomo Zvenyika A R, Nathoo Kusum J, Matibe Petronella, Mudenge Boniface, Loyevsky Mark, Gordeuk Victor R
Department of Chemical Pathology, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.
Am J Clin Nutr. 2005 Nov;82(5):1102-6. doi: 10.1093/ajcn/82.5.1102.
Iron deficiency is common in African children, but genetic variations affecting susceptibility have not been identified. The Q248H mutation in ferroportin, a cellular iron exporter regulated by iron status and inflammation, may be associated with high iron stores in African adults.
The study examined the prevalence of iron deficiency in African children in an area where malaria transmission is low to absent and investigated whether ferroportin Q248H provides protection from iron deficiency.
Complete blood counts, serum markers of iron status and inflammation, and ferroportin Q247H were measured in 208 preschool children in Harare, Zimbabwe. Iron deficiency was defined by serum ferritin and C-reactive protein (CRP) concentrations (definition 1) or by ferritin and the ratio of transferrin receptor to log10 ferritin (definition 2).
Q248H was present in 40 children (38 heterozygotes, 2 homozygotes), elevated CRP was present in 26 (12.5%), and iron deficiency was present in 50 (24.0%) (definition 1) or 55 (26.4%) (definition 2). The interaction between ferroportin Q248H and CRP was significant for ferritin concentrations (P = 0.027) in a 2-factor analysis of variance model. With elevated CRP, the estimated geometric mean (SE range) ferritin concentration was 74 (52-106) microg/L for Q248H heterozygotes but 24 (20-30) microg/L for wild-type subjects (P = 0.016). With normal CRP, the ferritin concentration was 16 (14-19) microg/L whether or not the mutation was present. After adjustment for age and weight-for-height z score, the odds ratio (OR) for iron deficiency in Q248H heterozygotes was not significant according to definition 1 (OR: 0.53; 95% CI: 0.18, 1.40; P = 0.222) or definition 2 (OR: 0.39; 95% CI: 0.14, 1.07; P = 0.068).
Any effect of Q248H in protecting against iron deficiency may be observable in children exposed to repeated inflammatory conditions. Further studies of iron status and ferroportin Q248H in African children are needed.
缺铁在非洲儿童中很常见，但尚未发现影响易感性的基因变异。铁转运蛋白中的Q248H突变是一种受铁状态和炎症调节的细胞铁输出蛋白，可能与非洲成年人的高铁储存有关。
本研究调查了疟疾传播率低或无疟疾传播地区非洲儿童的缺铁患病率，并研究铁转运蛋白Q248H是否能预防缺铁。
对津巴布韦哈拉雷的208名学龄前儿童进行了全血细胞计数、铁状态和炎症的血清标志物以及铁转运蛋白Q247H检测。缺铁的定义为血清铁蛋白和C反应蛋白（CRP）浓度（定义1）或铁蛋白以及转铁蛋白受体与铁蛋白log10的比值（定义2）。
40名儿童（38名杂合子，2名纯合子）存在Q248H，26名（12.5%）CRP升高，50名（24.0%）存在缺铁（定义1）或55名（26.4%）存在缺铁（定义2）。在双因素方差分析模型中，铁转运蛋白Q248H与CRP之间的相互作用对铁蛋白浓度有显著影响（P = 0.027）。CRP升高时，Q248H杂合子的估计几何平均（SE范围）铁蛋白浓度为74（52 - 106）μg/L，而野生型受试者为24（20 - 30）μg/L（P = 0.016）。CRP正常时，无论是否存在突变，铁蛋白浓度均为16（14 - 19）μg/L。根据定义1（比值比：0.53；95%置信区间：0.18，1.40；P = 0.222）或定义2（比值比：0.39；95%置信区间：0.14，1.07；P = 0.068），调整年龄和身高别体重Z评分后，Q248H杂合子缺铁的比值比无统计学意义。
Q248H在预防缺铁方面的任何作用可能在反复暴露于炎症的儿童中观察到。需要对非洲儿童的铁状态和铁转运蛋白Q248H进行进一步研究。
