孤独症谱系障碍儿童维生素B12及相关代谢产物MMA和转运蛋白TCN2的病例对照研究

探讨孤独症谱系障碍(ASD)儿童体内维生素B12水平,为ASD早期发现及药物治疗提供理论依据.方法 收集哈尔滨市ASD儿童和正常对照儿童各89人,应用酶联免疫吸附试验技术(ELISA)测定尿液甲基丙二酸(Methylmalonic acid,MMA)及血清维生素B12、转运蛋白转钴胺素蛋白Ⅱ(TranscobalaminⅡ,TCN2)的含量,应用SNaPshot对TCN2基因rs1801198位点进行基因分型.结果 ASD儿童的血清维生素B12和TCN2水平[(369.08±131.88)pmol/L,(1.56±0.16)ng/mL]均低于对照组儿童[(485.16±200.33)pmol/L,(1.71±0.17)ng/mL](t值分别为-5.47,-5.92,P值均<0.05),ASD儿童尿液中MMA水平[(758.97±106.96)ng/mL]高于对照组[(693.66±121.72)ng/mL](t=3.94,P<0.05);TCN2基因rs1801198位点基因多态性与ASD的患病风险的关联无统计学意义(P值均>0.05),与血清TCN2水平的关联无统计学意义(F=1.16,P>0.05).结论 ASD儿童维生素B12潜在缺乏,应在开展ASD干预的同时加强营养干预.

Case-control study of vitamin B12 and metabolite MMA and transporter TCN2 in children with ASD

Objective To investigate the level of vitamin B12 in children with autism spectrum disorder (ASD), and provide a theoretical basis for early detection and drug treatment of ASD. Methods A total of 89 ASD cases and 89 matched controls were collected. The levels of urinary methylmalonic acid (MMA) and serum vitamin B12, Transcobalamin Ⅱ (TCN2) were determined by enzyme-linked immunosorbent assay (ELISA). TCN2 gene rs1801198 was genotyped by SNaPshot. Results The serum levels of vitamin B12 and TCN2 in children with ASD [ (369.08±131.88) pmol/L, (1.56±0.16) ng/mL] were significantly lower than those in the control group[ (485.16±200.33) pmol/L, (1.71±0.17) ng/mL] (t=-5.47,-5.92, P<0.05). The level of MMA in urine of ASD children [ (758.97±106.96) ng/mL] was significantly higher than that in the control group[ (693.66±121.72) ng/mL] (t=3.94, P<0.05); The genetic polymorphism of rs1801198 locus was not associated with the risk of ASD (P>0.05), and there was no significant correlation with serum TCN2 level (F=1.16, P>0.05). Conclusion ASD children are at a potential deficiency of vitamin B12 and should strengthen their nutritional interventions while conducting ASD interventions.