用基因芯片检测DPYD等位基因在受试人群中的发生频率

二氢嘧啶脱氢酶基因（DPYD基因）所编码的二氢嘧啶脱氢酶（DPD酶）是氟化嘧啶类抗肿瘤药物代谢的主要限速酶，其活性存在显著的个体差异，并因此影响药物的疗效和毒副作用.大部分编码低/无活性酶的突变型等位基因是由于基因中的单核苷酸多态性（single nucleotide polymorphism，SNP）造成的，检测这些SNPs是预测患者对药物的反应和实现个体化给药方案的基础.制备并优化了用于检测DPYD基因中6个已知SNPs所编码的等位基因（DPYD^*2，^*3，^*4，^*5，^*9，^*12）的基因芯片，建立了该芯片的基因分型标准.并利用该芯片检测了肿瘤患者（112例）、肾病患者（83例）和健康者（45例）中DPYD突变型等位基因的发生频率.在受试人群中，突变型等位基因DPYD^*5和DPYD^*9平均发生率分别为32.08%和11.25%，未发现DPYD^*2，^*3，^*4，^*12突变型等位基因.而且以上单碱基突变的发生率在肿瘤患者、肾病患者和健康者间以及男性、女性肿瘤患者间无显著性差异，表明其与疾病的发生或性别无显著性关联.对20例标本的基因分型结果采用直接测序法进行验证，19例基因芯片分型结果与直接测序法结果相一致.DPYD^*5、DPYD^*9突变型等位基因在受试人群中具有较高的发生率.利用基因芯片能够对其实现快速准确的检测.

Frequency Detection of The Known DPYD Alleles in The Studied Subjects Using Oligonucleotide Microarray

DPD enzyme, encoded by the DPYD gene, is the major rate-limiting enzyme in the metabolism of the anti-cancer drugs. And it exists substantial inter-individual variations in its enzymatic activity. It was shown that mutant alleles of DPYD that encoding an inactive/decreased enzyme are largely caused by SNP (single nucleotide polymorphism) in the gene. Detection of the SNPs is the basis for the prediction of drug-response and realization of individualized therapeutic regimen for patients. For this reason an oligonucleotide microarray for genotyping 6 known SNPs of DPYD gene was optimized, and the genotyping standard for this microarray was fabricated. The microarray system was used to detect the mutant allelic frequency of DPYD in cancer patients (112 individuals), nephrotic patients (83 individuals) and healthy subjects(45 individuals). In the studied groups, the average frequencies for the mutant alleles of DPYD *5 and DPYD *9 are 11.25% and 32.08% respectively. No mutant alleles of DPYD *2, *3, *4, *12 were found. And there is no significant difference (P>0.05) in the mutation incidence in different subject groups or sex groups. The SNPs was shown to have no significant association with the disease and sex. The genotyping results of 20 samples were tested by direct sequencing, the genotyping results of 19 samples by miroarray were conformed with the direct sequencing. The allelic frequencies of DPYD *5 and DPYD *9 is high in the studied groups, quick and accurate detection of them can be achieved by using DNA microarray.