重庆市永川区3～6岁留守儿童25-羟维生素D水平及其与维生素D受体基因FOKⅠ位点多态性的相关性研究

Serum levels of 25-hydroxy vitamin D in 3 to 6-year-old left-behind children in Yongchuan District and its correlation with vitamin D receptor FOKⅠ genetic polymorphism

目的了解重庆市永川区乡镇3~6岁留守儿童维生素D营养状况,探讨维生素D受体基因FOKⅠ位点多态性与25-羟维生素D[25-(OH)D]的相关性。方法 2015年11月-2016年4月期间,由重庆医科大学附属永川医院招募永川区部分乡镇3~6岁留守儿童进行健康体检,以非留守儿童作为对照,采用液相色谱串联质谱法进行血清25-(OH)D水平检测,采用聚合酶链反应限制性片段长度多态性(PCR-RFLP)法进行FOKⅠ位点基因型检测。结果 1285例3~6岁留守儿童血清25-(OH)D平均水平为(19.566±5.185)ng/m L,维生素D充足占2.81%;不足组占41.40%;缺乏占52.98%;严重缺乏占2.81%。留守儿童组血清25-(OH)D较之非留守儿童组低,但两组比较无显著差异。其中3岁组25-(OH)D平均水平最高,各年龄组维生素D水平比较差异有统计学意义(P<0.001)。2ff基因型的维生素D水平较其余2种基因型低,但3种基因型的维生素D水平差异无显著统计学意义(P>0.05)。采用协方差分析校正年龄对维生素D水平的影响后,各基因型维生素D水平相比较差异仍无显著统计学意义(P>0.05)。结论重庆市永川区留守儿童25-(OH)D水平严重低下,需采取措施提高维生素D水平,VDR受体基因FOKⅠ位点多态性可能与25-(OH)D水平无关。

Objective To investigate the status and deficiency of 25-hydroxy vitamin D [ 25-（OH） D] in left-behind children at 3 -6 years old living in Yongchuan District, Chongqing, and to explore the correlation of vitamin D receptor （VDR） genetic polymorphism FOK I and serum levels of 25-（OH） D3. Methods A total of 285 left-behind children at the age of 3 to 6 living in some towns of Yongchuan District were recruited in our hospital during November 2015 to April 2016. They all took physical examination, and their serum level of 25-（OH） D was detected by liquid chromatography-tandem mass spectrometry. The genotypes of FOK I polymorphisms for VDR gene were analyzed with polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP）. Results ① The average serum level of 25-（ OH ）D was 19.566-＋5. 185 ng/mL in the 285 children, with 8 cases （2. 81%） sufficient, 118 cases （41.40%） insufficient, 151 cases （52.98%） deficient and 8 cases （2.81%） severely deficient. The level was lower in the left-behind children than the non-left-behind children, though no statistical difference. The level was the highest in the 3-yea-old group, and statistical differences were observed among the different age groups （P 〈 O. 001 ）. ② The serum level of 25-（OH） D was lower in the children with ff genotype than those with Ff and FF genotypes, but there was no statistical difference among different genotypes groups （P 〉 0. 05 ）. Covariance analysis indicated that there was no statistical difference in the serum level of 25-（OH） D among the different genotypes groups after adjustment of age （ P 〉 0.05 ）. Conclusion The serum level of 25- （OH） D is severely low in the left-behind children at the age of 3 to 6 in Yongchuan District. Some measures should be implied to improve the levels. Fok I polymorphisms in VDR gene might have no correlation with the serum level of 25-（OH） D.