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Dmitri Proudnikov

Publications and source records attributed to Dmitri Proudnikov.

5 recordsLinked to original sources
PubMed2006

Association analysis of polymorphisms in serotonin 1B receptor (HTR1B) gene with heroin addiction: a comparison of molecular and statistically estimated haplotypes.

OBJECTIVES: 5-Hydroxytryptamine (serotonin)-1B receptors (HTR1B) may play an important role in psychiatric disorders and drug and alcohol dependence. In this study we report on genotype, molecular haplotype and statistically estimated haplotype analyses of previously identified polymorphisms in positions -261T>G, -161A>T, 129C>T, 861G>C and 1180A>G of the HTR1B gene in ethnically diverse populations (African-Americans, Caucasians, Hispanics and Asians) including 235 former heroin addicts and 161 control subjects from New York City. The objectives were to test for an association of molecular and statistically estimated haplotypes and genotypes in HTR1B gene with heroin addiction and to compare results provided by molecular and statistically estimated haplotyping methods. METHODS: Genotype analysis was performed using a standard TaqMan protocol. Molecular haplotype analysis of the subset of polymorphisms consisting of -261T>G, -161A>T and 129C>T was performed using a protocol specially designed by our group, using fluorescent PCR. This is based on use of allele-specific primers complementary to flanking polymorphisms and a fluorescently labeled sequence-specific TaqMan probe set complementary to an internal polymorphism of the haplotype region. Every individual's statistically inferred haplotype pair agreed with the individual's haplotype pair determined by molecular haplotyping. RESULTS AND CONCLUSION: A point-wise significant association of haplotype pairs containing allele G at position 1180 with protective effect from heroin addiction in Caucasians was found. A point-wise nominally significant association of allele 1180G with a protective effect from heroin addiction was found in Caucasians. Statistically significant differences across four ethnic groups in control subjects for allelic frequencies of -261T>G and -161A>T were found.

Black or African American↗
PubMed2005

Increased attributable risk related to a functional mu-opioid receptor gene polymorphism in association with alcohol dependence in central Sweden.

The mu-opioid receptor (MOR), through its effects on reward and stress-responsivity, modulates alcohol intake in both animal and human laboratory studies. We have previously demonstrated that the frequently occurring A118G single-nucleotide polymorphism (SNP) in exon 1 of the MORgene (OPRM1), which encodes an amino-acid substitution, is functional and receptors encoded by the variant 118G allele bind the endogenous opioid peptide beta-endorphin with three-fold greater affinity than prototype receptors. Other groups subsequently reported that this variant alters stress-responsivity in normal volunteers and also increases the therapeutic response to naltrexone (a mu-preferring opioid antagonist) in the treatment of alcohol dependence. We compared frequencies of genotypes containing an 118G allele in 389 alcohol-dependent individuals and 170 population-based controls without drug or alcohol abuse or dependence. The A118G SNP was present in the Hardy-Weinberg equilibrium with an overall frequency of the 118G allele of 10.9%. There was a significant overall association between genotypes with an 118G allele and alcohol dependence (p=0.0074). The attributable risk for alcohol dependence in subjects with an 118G allele was 11.1%. There was no difference in A118G genotype between type 1 and type 2 alcoholics. In central Sweden, the functional variant 118G allele in exon 1 of OPRM1 is associated with an increased attributable risk for alcohol dependence.

Adult↗
PubMed2003

Quantification of multiple mRNA levels in rat brain regions using real time optical PCR.

TaqMan is significantly more sensitive than other methods of mRNA quantification and makes possible the simultaneous analysis of numerous genes in small brain regions. This technique was used to quantify levels of mRNAs of 21 genes in tissue extracts from caudate putamen and nucleus accumbens from individual rats after 1 day 'binge' cocaine or saline administration. Expression of glyceraldehyde-3-phosphate-dehydrogenase, cyclophilin and actin mRNAs as well as 18S ribosomal RNA were evaluated for normalization of levels of gene expression.

Animals↗
PubMed2003

Optimizing primer--probe design for fluorescent PCR.

TaqMan, a variation of fluorescent PCR, is a powerful tool for gene expression and polymorphism studies. Here we describe the design and evaluation of 27 new TaqMan primer-probe sets for rat genes that play a key role in neural signaling. These newly designed and synthesized probes were tested and then used for quantification of RNA isolated from rat brain. The usual length of common TaqMan probes is 25 bases or less. In these studies we constructed probes with lengths of 25-39 bases to span exon-exon junctions of nucleic acids to avoid the influence of DNA contamination upon the RNA quantification. The specific sequences at these positions required probes of these lengths to optimize hybridization. We found that the relocation of the quencher from the traditional 3' position to an internal one increases the sensitivity of probe up to 30 fold. Substitution of 6-carboxyfluorescein with Alexa Fluor 488 as fluorophore and TAMRA with non-fluorescent quencher dabcyl was also investigated. We also describe the evaluation of part of a newly designed set of 27 TaqMan primer-probes for the measurement of differences in gene expression levels in samples from the caudate putamen region of rat brain after 'binge' paradigm cocaine administration. Cocaine-induced alterations in expression of c-fos and preprodynorphin mRNAs measured by TaqMan were confirmed by ribonuclease protection assay.

Animals↗