Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.1.1.67 (thiopurine methyltransferase)
 551 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Genetic polymorphism among patients with acute lymphoblastic leukemia (ALL) is an important factor in the effectiveness and toxicity of anti-leukemic drugs. Genotyping of various polymorphisms that impact the outcome of anti-leukemic drug therapy (pharmacogenetics) presents an attractive approach for developing individualized therapy. We developed an easy and accurate method of analyzing multiple genes using a small amount of DNA, which we termed TotalPlex amplification. We used 16 pairs of specific bulging specific primers (SBS primers) for simultaneous amplification of 16 loci in a single PCR tube. Sixteen single nucleotide polymorphisms (SNPs) (CYP3A4*1B A>G, CYP3A5*3 G>A, GSTP1 313 A>G, GSTM1 deletion, GSTT1 deletion, MDR1 exon 21 G>T/A, MDR1 exon 26 C>T, MTHFR 677 C>T, MTHFR 1298 A>C, NR3C1 1088 A>G, RFC 80 G>A, TPMT 238 G>C, TPMT 460 G>A, TPMT 719 A>G, VDR intron 8 G>A, VDR FokI T>C) that have been implicated in the pharmacogenetics of ALL therapy were analyzed by TotalPlex amplification and SNP genotyping. We successfully amplified specific gene fragments using 16 pairs of primers in one PCR reaction tube with minimal spurious amplification products using TotalPlex amplification coupled to a multiplexed bead array detection system. The genotypes of 16 loci from 34 different genomic DNA (gDNA) samples derived using the TotalPlex system were consistent with the results of several standard genotyping methods, including automatic sequencing, PCR restriction fragment length polymorphism (RFLP) analysis, PCR, and allele-specific PCR (AS-PCR). Thus, the TotalPlex system represents a useful method of amplification that can improve the time, cost, and sample size required for high-throughput pharmacogenetic analysis of SNPs.
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PMID:TotalPlex gene amplification using bulging primers for pharmacogenetic analysis of acute lymphoblastic leukemia. 1838 10

Genetic polymorphisms are important factors in the effects and toxicity of chemotherapeutics. To analyze the pharmacogenetic and ethnic differences in chemotherapeutics, major genes implicated in the treatment of acute lymphoblastic leukemia (ALL) were analyzed. Eighteen loci of 16 genes in 100 patients with ALL were analyzed. The distribution of variant alleles were CYP3A4*1B (0%), CYP3A5*3 (0%), GSTM1 (21%), GSTP1 (21%), GSTT1 (16%), MDR1 exon 21 (77%), MDR1 exon 26 (61%), MTHFR 677 (63%), MTHFR 1298 (29%), NR3C1 1088 (0%), RFC1 80 (68%), TPMT combined genotype (7%), VDR intron 8 (11%), VDR FokI (83%), TYMS enhancer repeat (22%) and ITPA 94 (30%). The frequencies of single nucleotide polymorphisms (SNPs) of 10 loci were statistically different from those in Western Caucasians. Dose percents (actual/planned dose) or toxicity of mercaptopurine and methotrexate were not related to any SNPs. Event free survival (EFS) rate was lower in ITPA variants, and ITPA 94 AC/AA variant genotypes were the only independent risk factor for lower EFS in multivariate analysis, which was a different pharmacogenetic implication from Western studies. This study is the first pharmacogenetic study in Korean pediatric ALL. Our result suggests that there are other possible pharmacogenetic factors besides TPMT or ITPA polymorphisms which influence the metabolism of mercaptopurine in Asian populations.
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PMID:Pharmacogenetic analysis of pediatric patients with acute lymphoblastic leukemia: a possible association between survival rate and ITPA polymorphism. 2352 91

The standard treatment for autoimmune hepatitis (AIH) is predniso(lo)ne for remission induction, tapered and followed by azathioprine, which effectively controls the disease in the majority of patients. However, some patients prove to be unresponsive or non-tolerant and require alternative immunosuppressive regimens for disease control. We aimed to investigate whether these AIH patients who experience failure of standard treatment have a genomic basis for their problem in the form of pharmacogenetic variants. Fifty-six consecutive patients with AIH [41 female and 15 male; median age 42 years (12-76)] were retrospectively stratified according to being responders to standard therapy (n = 33) or patients with failure of standard therapy (n = 23). Their blood DNA was exome-captured and sequenced. Genomic variants were filtered and compared between the groups using Ingenuity Variant Analysis (3.1.20150407). The exome sequencing and data processing revealed glucocorticoid receptor signalling to be the most prominently affected pathway among the patients with failure of standard therapy (highly significant). Standard treatment failure was not associated with thiopurine S-methyltransferase variants or the HLA-DRB1*03 genotype. In conclusion, enrichment of variants related to glucocorticoid receptor signalling was a particular genomic trait of the AIH patients in whom standard treatment failed and alternative immunosuppression was required. If confirmed, a future application of this finding may be to identify prospective cases of failure of standard treatment already at diagnosis.
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PMID:Enrichment of Genetic Variants in the Glucocorticoid Receptor Signalling Pathway in Autoimmune Hepatitis with Failure of Standard Treatment. 2837 75

A biochip, primer set, and genotyping protocol were developed to simultaneously address 16 single nucleotide polymorphisms in antileukemic drug metabolism genes, including TPMT, ITPA, MTHFR, SLCO1B1, SLC19A1, NR3C1, GRIA1, ASNS, MTRR, and ABCB1. The genotyping procedure included a one-round multiplex polymerase chain reaction (PCR) with simultaneous incorporation of a fluorescent label into the PCR product and subsequent hybridization on a biochip with immobilized probes. The method was used to test 65 DNA samples of leukemia patients. Fluorescence signal intensity ratios in pairs of wild-type and respective mutant sequence probes were analyzed for all polymorphic markers and demonstrated high accuracy of genotyping. The reliability of genotype determination using the biochip was confirmed by direct Sanger sequencing.
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PMID:[Multiplex Genotyping of Allelic Variants of Genes Involved in Metabolizing Antileukemic Drugs]. 2969 92