红细胞己糖激酶缺乏症患者诊治的临床研究

Diagnosis of red blood cell hexokinase deficiency and literature review

目的 通过报道1例红细胞己糖激酶缺乏症患者的诊疗过程并复习相关文献,探讨基因测序及蛋白质构型研究在其诊断过程中的价值.方法 选择2016年5月23日于中山大学孙逸仙纪念医院儿科就诊并拟诊为红细胞己糖激酶缺乏症的1例患儿及其家系为研究对象.采用回顾性分析方法收集患儿相关临床资料.采用目标序列捕获和高通量第二代基因测序的方法筛查患儿致病基因,并且通过观察蛋白质三维结构的变化研究突变基因对己糖激酶功能的影响.结果 该患儿出生后存在慢性溶血性贫血.患儿DNA样本经高通量第二代基因测序结果显示,其10号染色体HK1基因第1号外显子第34位核苷酸由胞嘧啶突变为胸腺嘧啶,编码精氨酸的密码子突变为终止密码子：NM_033496：exon1：c.C34T：p.Arg12X,该突变为无义突变.经生物信息学分析和蛋白质功能模拟验证,证实该基因突变可导致肽链的合成提前终止,突变后合成的短肽不包含红细胞己糖激酶的结合基团和催化基团,导致酶的活性丧失.该患儿最终确诊为HK1基因突变所致红细胞己糖激酶缺乏性溶血性贫血.结论 在临床实践中,对于表现为慢性非球形红细胞性溶血性贫血的患者,需警惕红细胞己糖酶缺陷疾病.有条件者应行基因测序及蛋白质构型分析明确诊断.

Objective To investigate the value of gene sequencing and protein conformation in the diagnosis process by reporting a case of erythrocyte hexokinase deficiency and reviewing relevant literature.Methods One patient with erythrocyte hexokinase deficiency and his families in the pediatrics of Sun Yat-sen Memorial Hospital of Sun Yat-sen University on May 23,2016 were selected as the research objects.Clinical data was collected from the initial records by retrospective analysis.Pathogenic gene was detected by target sequence capture and next generation high-throughput sequencing,and the effects of mutant genes on hexokinase function were studied by observing changes in the 3-dimensional structure of proteins.Results The patient exhibited chronic hemolytic anemia after birth.The high-throughput second-generation gene sequencing result of the DNA sample of the child showed that a de novo mutation in the HK1 gene located on chromosome 10,the substitution of cytidine at site 34 of exon1 by thymine：NM_033496：exon1：c.C34T：p.Arg12X,which was a nonsense mutation.Bioinformatics analysis and protein function simulation confirmed that the mutation of the gene can lead to the premature termination of the synthesis of the peptide chain.The short peptide synthesized after the mutation does not contain the binding group and catalytic group of the erythrocyte hexokinase,resulting in the loss of enzyme activity.The patient was eventually diagnosed with erythrocyte hexokinase-deficient hemolytic anemia caused by the HK1 gene mutation.Conclusions In clinical practice,patients with chronic non-spherical erythrocyte hemolytic anemia should be alert to erythrocyte hexosaminidase deficiency disease.Those with conditions should be diagnosed by gene sequencing and protein configuration analysis.