Development of a Polymerase Chain Reaction/Ligase Detection Reaction Assay for Detection of CYP2C19 Polymorphisms

AIMS

Cytochrome P450 2C19 (CYP2C19) genotypes are associated with differential drug metabolism. The aim of this study was to establish a reliable assay for CYP2C19 genotyping based on a polymerase chain reaction/ligase detection reaction (PCR-LDR).

MATERIALS AND METHODS

Specific primers and probes were designed to detect CYP2C19*1, *2, *3, and *17. A control for each allele was prepared and used for performance evaluation. A total of 200 clinical samples were analyzed using the PCR-LDR assay and Sanger sequencing.

RESULTS

The detection limit of the PCR-LDR assay was 2 ng/μL of genomic DNA. Common interfering substances in the blood did not affect the results of the detection. For the clinical samples, the results of the PCR-LDR and the Sanger sequencing were identical. Among the 200 patients, 104 (52%) were wild type (*1/*1), 64 (32%) were *1/*2, 16 (8%) were *1/*3, 8 (4%) were *2/*2, 7 (3.5%) were *2/*3, and 1 (0.5%) was *1/*7. No *3/*3 genotype was detected in these patients.

CONCLUSION

This PCR-LDR assay is reliable for the detection of CYP2C19 genotypes in a clinical setting. It will be a useful tool to screen for CYP2C19 loss-of-function alleles in patients before clopidogrel and proton pump inhibitor treatment.

Three common functional polymorphisms in microRNA encoding genes in the susceptibility to hepatocellular carcinoma: a systematic review and meta-analysis

Emerging evidences have shown that common genetic polymorphisms in microRNAs may be associated with the development of hepatocellular carcinoma (HCC); but individually published studies and previous meta-analyses revealed inconclusive results. The aims of this review and meta-analysis are to assess whether common single-nucleotide polymorphisms (SNPs) in the genes encoding the microRNAs are associated with susceptibility to HCC development and clinicopathologic characteristics of hepatitis B virus (HBV) related HCC. A computerized search was performed in PubMed, Embase, Web of Science and China BioMedicine (CBM) databases to identify relevant articles published before January 1st 2013. Ten case-control studies were assessed with a total of 3437 cases and 3437 healthy controls. Three common functional SNPs in miRNA-encoding genes were found, including miR-146a G>C (rs2910164), miR-196a-2 C>T (rs11614913) and miR-499 T>C (rs3746444). This meta-analysis revealed that the miR-146a C variant was associated with a decrease in HCC risk, especially among Asian and male populations; while the miR-196a-2 T variant was associated with susceptibility to HCC among Caucasian populations. However, we failed to find any significant correlations between the miR-499 C polymorphism and HCC risks. When further stratification on HBV status was conducted, a similar trend of association between the three SNPs and the HBV-related HCC risks was observed, but these results were not statistically significant due to small sample sizes. The current meta-analysis demonstrates that SNPs contained in the genes encoding miR-146a and miR-196a-2 may play a major role in genetic susceptibility to HCC.

Three common functional polymorphisms in microRNA encoding genes in the susceptibility to hepatocellular carcinoma: a systematic review and meta-analysis

Emerging evidences have shown that common genetic polymorphisms in microRNAs may be associated with the development of hepatocellular carcinoma (HCC); but individually published studies and previous meta-analyses revealed inconclusive results. The aims of this review and meta-analysis are to assess whether common single-nucleotide polymorphisms (SNPs) in the genes encoding the microRNAs are associated with susceptibility to HCC development and clinicopathologic characteristics of hepatitis B virus (HBV) related HCC. A computerized search was performed in PubMed, Embase, Web of Science and China BioMedicine (CBM) databases to identify relevant articles published before January 1st 2013. Ten case-control studies were assessed with a total of 3437 cases and 3437 healthy controls. Three common functional SNPs in miRNA-encoding genes were found, including miR-146a G>C (rs2910164), miR-196a-2 C>T (rs11614913) and miR-499 T>C (rs3746444). This meta-analysis revealed that the miR-146a C variant was associated with a decrease in HCC risk, especially among Asian and male populations; while the miR-196a-2 T variant was associated with susceptibility to HCC among Caucasian populations. However, we failed to find any significant correlations between the miR-499 C polymorphism and HCC risks. When further stratification on HBV status was conducted, a similar trend of association between the three SNPs and the HBV-related HCC risks was observed, but these results were not statistically significant due to small sample sizes. The current meta-analysis demonstrates that SNPs contained in the genes encoding miR-146a and miR-196a-2 may play a major role in genetic susceptibility to HCC.