La schizophrénie est une pathologie sévère et fréquente. Elle constitue un problème majeur de santé publique. Les traitements disponibles présentent des problèmes de tolérance non négligeables et leur efficacité reste modérée. La recherche en pharmacogénétique des antipsychotiques a pour objectif d’aider les prescripteurs à choisir les traitements de façon plus rationnelle. Les carences méthodologiques des premières études réalisées expliquent sans doute le peu de résultat répliqué à ce jour. Dans une cohorte de patients schizophrènes caucasiens traités par olanzapine ou rispéridone et évaluée prospectivement pour l’efficacité et la tolérance du traitement, nous avons d’abord recherché des critères cliniques permettant de prédire la réponse au traitement. L’age précoce de début des troubles et la durée de la maladie sont des prédicteurs individuels de la mauvaise réponse au traitement. Nous avons également étudié l’implication de variants génétiques du transporteur de la noradrénaline dans l’efficacité des traitements. Nous avons observé l’implication de deux polymorphismes dans la décroissance des symptômes positifs sous traitement. L’analyse de l’impact du variant C825T de la GNB3 dans la prise de poids sous antipsychotique n’a pas retrouvé d’association significative. Enfin, nous avons étudié l’ensemble des variants alléliques du cytochrome P450 2D6 dans cette cohorte de patients schizophrènes comparée à des témoins. L’allèle CYP2D6*2 était associé à un effet protecteur vis à vis de la schizophrénie. Les associations retrouvées devraient aider à mieux comprendre les mécanismes physiopathologiques impliqués dans la schizophrénie et la réponse au traitement / Schizophrenia is a frequent and severe disease. It constitutes a major public health problem. All the available treatments however, have significant adverse side-effects and their efficacy remains moderate. The aim of pharmacogenetic research is to help practitioners to choose treatments in a more rational way. The methodological limits of the first published studies probably explain the lack of replication of such studies. In a prospective study of a sample of Caucasian schizophrenic patients treated with olanzapine or risperidone, clinical criteria were assessed as factors that may predict drug response. Early onset and duration of the disease, individually predicted an unfavourable drug response. We also studied genetic variants of the norepinephrine transporter to see how they may affect antipsychotic drug efficacy. Two polymorphisms were associated with a reduction in positive symptoms in treated schizophrenic patients. No association between the GBN3 C825T variant and weight gain in patients treated by antispychotic drugs was observed. Finally, we genotyped all the cytochrome P450 2D6 allelic variants in the same Caucasian schizophrenic sample and a Caucasian origin control cohort. The CYP2D6*2 allele was strongly associated with protection towards schizophrenia. The two observed associations may help to better understand the still unwell known physiopathological mechanisms implicated in schizophrenia aetiology and antipsychotic drug response

Genetische Polymorphismen in den Enzymen CYP2D6, CYP2C19 und CYP2C9 beeinflussen die Pharmakokinetik medizinisch bedeutsamer Arzneimittel wie Antidepressiva, oraler Antidiabetika und nichtsteroidaler Antiphlogistika in erheblichem Ausmaß. In der Zukunft kann die Bestimmung genetischer Varianten bei Patienten zur Verbesserung der Arzneitherapie genutzt werden, jedoch nur dann, wenn klinische Konsequenzen wie konkrete Therapieempfehlungen aus den genetischen Daten abgeleitet werden können. An gesunden Probanden wurde die die Bedeutung der beiden Aminosäurevarianten des Enzyms CYP2C9, Arg144Cys (CYP2C9*2) und Leu359Ile (CYP2C9*3) für die Pharmakokinetik von Tolbutamid, Glibenclamid, Nateglinid, Diclofenac, Ibuprofen, Celecoxib und Fluvastatin untersucht. Die Analyse der pharmakokinetischen Parameter ergab eine erheblich erniedrigte Clearance für diese Substrate bei homozygoten Trägern der Allelvariante CYP2C9*3, wie sie etwa 1% in der Bevölkerung tragen. Um bioäquivalente Konzentrationsverläufe zu erreichen, müssten diese Patienten deutlich niedrigere Dosierungen (unter 50%) der meisten der untersuchten CYP2C9-Substrate erhalten. Hingegen zeigte die CYP2C9*2-Variante nur einen geringen Einfluss auf die Pharmakokinetik der untersuchten Medikamente. Für den Bereich der Therapie mit Antidepressiva und Antipsychotika sollte untersucht werden, inwieweit umfassende pharmakogenetisch begründete Therapieempfehlungen gegeben werden können. Eine systematische Analyse aller bisher publizierten Daten zum Einfluss von Polymorphismen von CYP2D6, CYP2C19 und CYP2C9 ergab, dass für die meisten gängigen Antidepressiva bereits Studien zur Bedeutung von Cytochrom-P450-Polymorphismen durchgeführt wurden. Für die beiden in Deutschland sehr häufig verwendeten Trizyklika Trimipramin und Doxepin dagegen lagen keine ausreichenden Daten vor. Beide Medikamente wurden deshalb bei Probanden getestet, die jeweils Träger eines oder zweier Allele mit defizienter oder herabgesetzter Enzymaktivität von CYP2D6, CYP2C19 oder CYP2C9 waren. Es ergab sich ein deutlicher Einfluss des CYP2D6-Genotyps, ein schwächerer von CYP2C19 und des Genotyps CYP2C9*3/*3. Eine Dosisreduktion für Langsam-Metabolisierer von CYP2D6 und etwas moderater für Langsam-Metabolisierer von CYP2C19, sowie für Träger des Genotyps CYP2C9*3/* erscheint für diese beiden Antidepressiva sinnvoll. Die eigenen Daten und die Daten für andere Antidepressiva aus der Literatur wurden dazu verwendet, eine Methode zur Ableitung von pharmakogenetisch basierten Dosierungsempfehlungen zu entwickeln. Auf dem Prinzip der Bioäquivalenz basierend wurden Dosierungsanpassungen für unterschiedliche Genotypen je nach Unterschieden in der Clearance von Substanzen errechnet. Durch diese Dosierungsanpassungen können zumindest theoretisch die durch herabgesetzte Enzymaktivität verursachten Unterschiede in den Plasmakonzentrationsverläufen von Medikamenten ausgeglichen werden. Dabei wurden aktive an der Arzneimittelwirkung teilhabende Metaboliten mit berücksichtigt. Auf Seiten der Pharmakodynamik wurden die vielen Studien zu genetischen Polymorphismen in Serotonin-, Dopaminrezeptoren und Transportern und auch zu anderen Kandidatengenen für die Antidepressiva-, und Antipsychotikawirkung analysiert. Jedoch lassen sich aus den teilweise geringen Einflüssen einzelner Genotypen auf die Arzneimittelwirkung derzeit noch keine pharmakodynamisch begründeten Therapieempfehlungen ableiten. Zusammenfassend lassen sich also bereits heute pharmakogenetisch basierte Dosierungsempfehlungen für viele Medikamente berechnen. Derartige Empfehlungen müssen prospektiv überprüft, validiert und angepasst werden. Auf Seiten der Zielmoleküle der Arzneimittelwirkung ist eine Ableitung genetisch basierter Therapieempfehlungen schwieriger. Das Ziel, konkrete Therapieempfehlungen aus genetischen Daten abzuleiten, ist eine notwendige Bedingung, um Pharmakogenetik in die klinische Praxis der Arzneitherapie einzuführen. / Genetic polymorphisms of the cytochrome P450 enzymes CYP2D6, CYP2C19 and CYP2C9 largely influence pharmacokinetics of clinically important drugs such as antidepressants, oral antidiabetics and nonsteroidal antiphlogistic drugs. Pharmacogenetic diagnostics is ready to be used for optimization of drug treatment in the future if concise recommendations for clinical decisions can be derived from the genetic data. Panel studies in healthy volunteers served to characterize the impact of the amino acid variants Arg144Cys (CYP2C9*2) and Leu359Ile (CYP2C9*3) in cytochrome P450 2C9 on pharmacokinetics of the oral antidiabetics tolbutamide, glyburide and nateglinide, of the nonsteroidal analgetic drugs diclofenac, ibuprofen, celecoxib, and of fluvastatin. Analysis of pharmacokinetic parameters revealed largely reduced oral clearances in homozygous carriers of the CYP2C9*3 allele for most of the substrates studied. About 1% in the general population are carriers of this genotype and patients should get about 50% lower doses of most of the CYP2C9 substrates in order to achieve similar plasma concentration versus time courses. In contrast, the CYP2C9*2 variant had little influence on pharmacokinetics of the CYP2C9 substrates. For antidepressant and antipsychotic drug therapy, the aim was to derive detailed dose recommendations from the large amount of data existing. Thus, a systematic analysis of all published data on the clinical influence of genetic polymorphisms in CYP2D6, CYP2C19 and CYP2C9 was performed and dose recommendations were given for many antidepressants. For two substances, the tricyclics doxepin and trimipramine, no pharmacogenetic data have been found, and therefore own clinical studies were performed. Healthy volunteers who were heterozygous and homozygous carriers of alleles with deficient activity of CYP2D6, CYP2C19 or CYP2C9 were tested for differences in metabolism and elimination of doxepin and trimipramine and compared to carriers of the wildtype. A significant influence of the CYP2D6 genotype was detected whereas CYP2C19 and the genotype CYP2C9*3/*3 had smaller influences. A significant dose reduction for CYP2D6 poor metabolizers and a smaller reduction for CYP2C19 poor metabolizers would be predicted from these data. According the principles of bioequivalence, calculation methods for pharmacogenetic based dose recommendations from clearance or drug concentration data were developed. Using all published data and the own study results, we developed dose adjustments for each genotype. These dose adjustments would allow to compensate for lower drug clearance caused by genetic variants. Active metabolites which contribute to overall drug effects were considered as well. With regard to target molecules of antidepressant and antipsychotic drug action, many studies have been performed on genetic polymorphisms in serotonin-, and dopamine receptors and in transporter molecules but as well in other candidate genes. However, it is not yet possible to derive therapeutic consequences based on these data. In conclusion, on the pharmacokinetic side of drug action, we are already able to give pharmacogenetic based therapeutic recommendations by adjusting the doses according to genotype. However, the benefit of pharmacogenetic dose adjustments has to be studied prospectively. With regard to the pharmacodynamic side of drug action, the situation is much more complex and we are not yet ready to give pharmacogenetics based therapeutic guidelines. However, this has to be a major goal in order to introduce pharmacogenetic diagnostic into clinical practice.

Alterações morfológicas no tecido ósseo têm sido descritas nos usuários de hipoglicemiantes orais da classe das tiazolidinedionas (TZDs). Hipotetiza-se que alguns genes relacionados com a osteogênese e osteoclastogênese podem ser influenciados pelo tratamento farmacológico, entretanto, o exato mecanismo ainda não está bem esclarecido. O objetivo do estudo foi avaliar o efeito da pioglitazona no remodelamento ósseo através de genes envolvidos na osteoclastogênese em indivíduos recentemente diagnosticados com DM2 e modelos animais, com a finalidade de identificar marcadores genéticos sensíveis de alterações ósseas. Foram convidados para participar do estudo 199 indivíduos (100 diabéticos e 99 normoglicêmicos), no ambulatório de dislipidemias do Instituto Dante Pazzanese de Cardiologia. Os indivíduos diabéticos foram tratados com pioglitazona (15, 30, 45, 45 mg/ dia/ via oral) por 16 semanas. Foram colhidas amostras de sangue, antes e após o tratamento para avaliações laboratoriais, extração de DNA genômico e de RNA total. Os polimorfismos e a expressão do mRNA nas células sanguíneas foram determinados pela PCR em tempo real através do sistema TaqMan®. Para o estudo em modelo animal após a indução da dieta hiperlipídica por 32 semanas, foram utilizados 12 camundongos machos da linhagem C57BL/J6, os quais foram divididos em três grupos: controle (n=4); diabéticos induzidos pela dieta hiperlipídica (DH, n=4) e diabéticos induzidos pela dieta hiperlipídica e tratados com pioglitazona 35mg/Kg/dia por 16 semanas (DHP, n=4). Para os grupos experimentais foram colhidos: amostras de sangue, para exames laboratoriais; fêmures, para a extração do RNA total; e tíbias, para determinação dos parâmetros histomorfométricos. Os pacientes DM2 apresentaram diminuição nas concentrações séricas de osteocalcina e na expressão de OPG e aumento na expressão de VDR em comparação ao grupo NG (p<0,05). A expressão de RANKL e IL6 foi maior entre as mulheres, enquanto que a expressão de PPARG foi maior entre os homens com DM2 em comparação ao grupo NG (p=0,032). Pacientes DM2 antes do tratamento apresentaram glicemia e expressão do mRNA de IL6 negativamente associados ao cálcio ionizado, enquanto que as transcrições de TNFA e VDR foram associadas positivamente e negativamente com bALP respectivamente (p<0,05). O tratamento com pioglitazona reduziu a glicemia de jejum, glicemia pós-prandial, insulina, HOMA-IR, triglicerídeos, VLDL-C, tALP e bALP e aumentou a HDL, tACP, TNF-&#945; e a transcrição de OPG (p<0,05). A glicemia basal associou-se positivamente com o cálcio ionizado. A expressão basal de OPG foi associado negativamente com tALP, enquanto que a expressão basal de TNFA foi associada positivamente com tALP e negativamente com tACP. A expressão basal IL6 foi associada positivamente com tALP, enquanto que a expressão basal de VDR foi associada negativamente com osteocalcina e positivamente com bALP em resposta ao tratamento (p<0,05). O polimorfismo RANK rs1805034 foi associado com redução na transcrição do gene RANK nos indivíduos DM2 e com o remodelamento ósseo após o tratamento com pioglitazona (p<0,05). O polimorfismo RANKL rs9525641 foi associado com aumento da transcrição gênica de RANKL nos indivíduos NG e DM2 e melhora da resposta farmacológica nos indivíduos DM2 tratados com pioglitazona (p<0,05). O polimorfismo rs3102735 do gene OPG foi associado com aumento da formação óssea nos indivíduos DM2 antes e após o tratamento (p<0,05). O genótipo CG do polimorfismo OPG rs2073618 foi associado com alteração da transcrição de OPG no grupo DM2 pré e pós-tratamento (p<0,05). O polimorfismo PPARG rs1801282 foi associado com menor risco para o desenvolvimento de diabetes (p<0,05). O polimorfismo PPARG rs2972162 foi associado com melhora da resistência insulínica nos indivíduos DM2 tratados com pioglitazona (p=0,017). O polimorfismo ESRI rs9340799 foi associado com redução da formação óssea nos indivíduos DM2 (p=0,038). Nos camundongos, após a indução da dieta hiperlipídica por 32 semanas, observou-se aumento do peso, da glicemia, do colesterol total, da expressão do mRNA de RANK, RANKL, IL6 e TNFA em fêmures e aumento de Tb.Sp e diminuição de BV/TV em comparação ao grupo controle (p<0,05). O tratamento com pioglitazona diminuiu a expressão de TNFA (p=0,028). As medidas histomorfométricas não alteraram-se após o tratamento (p>0,05). Os resultados sugerem que o estado hiperglicêmico e o tratamento influenciam os marcadores bioquímicos e moleculares. Os polimorfismos dos genes RANK, RANKL, OPG e ESRI parecem estar envolvidos no remodelamento ósseo independentemente da hiperglicemia e do tratamento e os polimorfismos do gene PPARG parecem estar envolvidos com menor risco para desenvolver diabetes e com a melhora da resistência insulínica em resposta ao tratamento com pioglitazona. / Morphological changes in bone tissue have been reported in users of oral hypoglycemic class of thiazolidinediones (TZDs). It is hypothesized that some genes related to osteogenesis and osteoclastogenesis may be influenced by pharmacological treatment, however, was not aware exact mechanism. The study aims was to evaluate pioglitazone effect on bone remodeling through genes involved in osteoclastogenesis in individuals newly diagnosed with DM2 and animal models, in order to identify sensibles genetics markers of bone alterations. Were invited to participate in study 199 patients (100 diabetics and 99 normoglycemic), in dyslipidemia ambulatory of Institute Dante Pazzanese of Cardiology. Diabetic subjects were treated with pioglitazone (15, 30, 45 or 45 mg /day/oral) for 16 weeks. Blood samples were collected before and after treatment for laboratory evaluations, extraction of genomic DNA and total RNA. Polymorphisms and mRNA expression in blood cells was determined by real time PCR using TaqMan® system. For study in animal model after 32 weeks of fat diet induction, was used 12 male mice C57BL/J6, which were divided into three groups: control (n=4); induced diabetic fat diet (DH, n=4) and induced diabetic fat diet and treated with pioglitazone 35mg/Kg/day for 16 weeks (DHP, n=4). For experimental groups were collected: blood samples for laboratory tests; femurs, for extraction of total RNA; and tibias, to determine histomorphometric parameters. DM2 patients showed decrease in serum osteocalcin and OPG expression and increased VDR expression compared to NG group (p<0.05). RANKL and IL6 expression were higher among women, whereas PPARG expression was higher among men with DM2 compared to NG group (p=0,032). DM2 patients before treatment showed blood glucose and IL6 mRNA expression negatively associated with ionized calcium, whereas TNFA and VDR transcription are positively and negatively associated with bALP respectively (p<0.05). Pioglitazone treatment reduced fasting glucose, postprandial glucose, insulin, HOMA-IR, triglycerides, VLDL-C, tALP and bALP and increased HDL, tACP, TNF-&#945; and OPG transcription (p<0.05). Basal blood glucose was positively associated with ionized calcium. Basal OPG expression was negatively associated with tALP, whereas basal TNFA expression was positively associated with tALP and negatively with tACP. Basal IL6 expression was positively associated with tALP, whereas basal VDR expression was negatively associated with osteocalcin and positively with bALP in response to treatment (p<0.05). RANK rs1805034 polymorphism was associated with RANK gene transcription reduction in subjects with DM2 and bone remodeling after treatment with pioglitazone (p<0.05). RANKL rs9525641 polymorphism was associated with increased RANKL gene transcription in NG and DM2 subjects and pharmacological response improvement in DM2 subjects treated with pioglitazone (p<0.05). OPG rs3102735polymorphism was associated with increased bone formation in DM2 subjects before and after treatment (p<0.05). CG genotype of OPG rs2073618 polymorphism was associated with OPG transcription change in DM2 group before and after treatment (p<0.05). PPARG rs1801282 polymorphism was associated with lower risk for diabetes development (p<0.05). PPARG rs2972162 polymorphism was associated with insulin resistance improvement in DM2 subjects treated with pioglitazone (p=0,017). ESRI rs9340799 polymorphism was associated with reduced bone formation in DM2 subjects (p=0,038). In mice, after 32 weeks of fat diet induction, was observed increase weight, blood glucose, total cholesterol and RANK, RANKL, IL6 and TNFA mRNA expression in femurs and Tb.Sp increase and BV/TV decrease compared to control group (p<0.05). Treatment with pioglitazone decrease TNFA (p=0,028). Histomorphometrics measurements not change after treatment (p>0.05). Results suggest that hyperglycemic state and treatment influence biochemical and molecular markers. RANK, RANKL, OPG and ESRI polymorphisms seens to be involved in bone remodeling regardless of hyperglycemia and treatment and PPARG gene polymorphisms seens to be associated with lower risk for diabetes development and with insulin resistance improvement in response to treatment with pioglitazone.

<p>The aim of this study was to investigate the genetic diversity of the SLC22A1 gene and to deduce its possible pharmacogenetic implications within the Cape Coloured population of South&nbsp / Africa / a uniquely admixed population of immigrant Europeans, Asians and the indigenous populations. Recent studies have reported an abundance of polymorphic variants within this solute&nbsp / carrier transporter gene encoding for the organic cation transporter 1, as well as evidence linking these variants to an effect on metformin uptake. This study included establishing baseline&nbsp / frequency distribution of previously reported alleles for 20 SNP variants within the SLC22A1 gene, as well as the development of SNaPshot&reg / and Multiplex AS-PCR genotyping assays, and&nbsp / also exploring the possibility of using High-resolution melt (HRM) analysis as a costeffective alternative for SNP genotyping. Ethics clearance was obtained from the Ethics Committee of the&nbsp / University of the Western Cape. Biological samples in the form of buccal (oral) swabs were collected from 132 unrelated voluntary donors from the Cape Coloured population residing in the&nbsp / Cape Metropolitan area. Two SNaPshot&reg / Multiplex Systems were specifically designed for the study,successfully optimized and used for genotyping. Hundred genetic profiles were then generated for a total of 20 SNP variants on SLC22A1 gene, using this primer extension-based genotyping method that enables multiplexing up 10 SNPs. Population genetics data obtained for&nbsp / the investigated SNPs were analysed using various statistical analysis software. Important population genetic parameters were calculated, and possible pharmacogenetics implications were then discussed. Among others, allelic and genotypic frequencies, as well as linkage disequilibrium were determined and compared with world populations. Minor deviation from Hardy- Weinberg equilibrium was observed in the Cape Coloured population. No significantLinkage Disequilibrium between the investigated SNPs was observed in this population. A Multiplex allele specific &ndash / PCR (MAS-PCR) genotyping&nbsp / system was successfully designed and optimized for the genotyping of 10 SNPs from the SLC22A1. This system, also developed specifically for this study, was made of 2 multiplexes each covering 5 SNPs. It is an inexpensive genotyping assay that allows for efficient discrimination of SNP polymorphisms in one reaction tube with standard PCR conditions. A pilot study was&nbsp / conducted to explore the possibility of using High-resolution melt (HRM) analysis as a cost-effective alternative for SNP genotyping. In addition to genotyping, HRM analysis can be used to scan&nbsp / large numbers of samples for novel genetic variations.&nbsp / </p>

Le busulfan (Bu) est un composé clé de la phase de conditionnement chez les enfants subissant une transplantation des cellules souches hématopoïétiques (TCSH). Les différences inter-individuelles de la pharmacocinétique (PK) du Bu pourraient affecter son efficacité et sa toxicité. Le Bu est principalement métabolisé par la glutathion-S-transférase (GST). Nous avons étudié la relation des génotypes GSTA1, GSTM1 et GSTP1 avec la PK de la première dose de Bu et la relation avec les résultats de la TCSH chez 69 enfants recevant un régime de conditionnement myéloablatif. Le génotype GSTM1 nul a corrélé avec une exposition élevée du Bu et une faible clairance (CL) chez les patients âgés de 4 ans (p ≤ 0,04). Dans le respect du rôle fonctionnel suggéré d’haplotype GSTA1 *A2, il a été associé à des niveaux plus faibles de médicaments et des niveaux élevés de CL (p ≤ 0,03). L’effet Gène-dose a également été observé (p = ≤ 0,007). L’haplotype de GSTA1 était associé avec les résultats de la TCSH. Les porteurs de deux copies d’haplotype *A2 avaient une meilleure survie sans événement (p = 0,03). En revanche, les individus homozygotes pour haplotypes * B et *B1 ont un risque plus élevé d’atteindre la maladie veino-occlusive (MVO) (p = 0,009). Les individus porteurs de GSTM1 nul âgés de 4 ans possèdent un risque plus fréquent d’avoir la maladie du greffon contre l'hôte (GvHD) (p = 0,03). En conclusion, nous avons montré que les variantes génétiques de GST influencent la PK du BU et les résultats de la TCSH chez les enfants. Pour l'ajustement de la posologie, un modèle avec l'inclusion des facteurs génétiques et non génétiques devrait être évalué et validé dans une étude prospective. / Busulfan (Bu) is a key compound of conditioning regimen in children undergoing hematopoietic stem cell transplantation (HSCT). Inter-individual differences in Bu pharmacokinetics might affect Bu efficacy and toxicity. Since Bu is mainly metabolized by glutathione S-transferase (GST), we investigated the relationship between GSTA1, GSTM1 and GSTP1 genotypes with first-dose Bu pharmacokinetics (PK), and relationship with HSCT outcomes in 69 children receiving myeloablative conditioning regimen. GSTM1 null genotype correlated with higher Bu exposure and lower clearance in patients older than 4 years (p≤0.04). In accordance with the suggested functional role GSTA1*A2 haplotype was associated with lower drug levels and higher drug clearance (p≤0.03). Gene-dosage effect was also observed (p=≤0.007). GSTA1 haplotypes were associated with HSCT outcomes Patients with two copies of haplotype *A2 had better event free survival (p=0.03). In contrast, homozygous individuals for haplotypes *B and *B1 had higher occurrence of veno-occlusive disease (p=0.009). GSTM1 null individuals older than 4 years had more frequently graft versus host disease (p=0.03). In conclusion, we showed that GST gene variants influence Bu PK and outcomes of HSCT in children. A model for the dosage adjustment with the inclusion of genetic and non-genetic factors should be evaluated in a future prospective validation cohort.

<p>The aim of this study was to investigate the genetic diversity of the SLC22A1 gene and to deduce its possible pharmacogenetic implications within the Cape Coloured population of South&nbsp / Africa / a uniquely admixed population of immigrant Europeans, Asians and the indigenous populations. Recent studies have reported an abundance of polymorphic variants within this solute&nbsp / carrier transporter gene encoding for the organic cation transporter 1, as well as evidence linking these variants to an effect on metformin uptake. This study included establishing baseline&nbsp / frequency distribution of previously reported alleles for 20 SNP variants within the SLC22A1 gene, as well as the development of SNaPshot&reg / and Multiplex AS-PCR genotyping assays, and&nbsp / also exploring the possibility of using High-resolution melt (HRM) analysis as a costeffective alternative for SNP genotyping. Ethics clearance was obtained from the Ethics Committee of the&nbsp / University of the Western Cape. Biological samples in the form of buccal (oral) swabs were collected from 132 unrelated voluntary donors from the Cape Coloured population residing in the&nbsp / Cape Metropolitan area. Two SNaPshot&reg / Multiplex Systems were specifically designed for the study,successfully optimized and used for genotyping. Hundred genetic profiles were then generated for a total of 20 SNP variants on SLC22A1 gene, using this primer extension-based genotyping method that enables multiplexing up 10 SNPs. Population genetics data obtained for&nbsp / the investigated SNPs were analysed using various statistical analysis software. Important population genetic parameters were calculated, and possible pharmacogenetics implications were then discussed. Among others, allelic and genotypic frequencies, as well as linkage disequilibrium were determined and compared with world populations. Minor deviation from Hardy- Weinberg equilibrium was observed in the Cape Coloured population. No significantLinkage Disequilibrium between the investigated SNPs was observed in this population. A Multiplex allele specific &ndash / PCR (MAS-PCR) genotyping&nbsp / system was successfully designed and optimized for the genotyping of 10 SNPs from the SLC22A1. This system, also developed specifically for this study, was made of 2 multiplexes each covering 5 SNPs. It is an inexpensive genotyping assay that allows for efficient discrimination of SNP polymorphisms in one reaction tube with standard PCR conditions. A pilot study was&nbsp / conducted to explore the possibility of using High-resolution melt (HRM) analysis as a cost-effective alternative for SNP genotyping. In addition to genotyping, HRM analysis can be used to scan&nbsp / large numbers of samples for novel genetic variations.&nbsp / </p>

Ziel: Entwicklung eines gesundheitsökonomischen Evaluationskonzepts zum Nachweis einer Kostenreduktion unter gleichzeitiger Optimierung des medizinischen Nutzens durch pharmakogenetisches Screening bei Erstdiagnose einer Schizophrenie. Finale Zielsetzung ist die Aufnahme der pharmakogenetischen a priori-Diagnostik für die Indikation Schizophrenie in die GKV-Regelversorgung. Methodik: Basierend auf dem aktuellen Stand gendiagnostischer Forschung sowie der evidenzbasierten Schizophrenietherapie wurde eine prospektive, randomisierte und kontrollierte, dreiarmige, offene, multizentrische Pilotstudie im Paralleldesign über 3 Jahre konzeptioniert. Studienpopulation: 300 Patienten (1:1:1) im Alter von 18 bis 65 Jahren mit erstmaliger F20-Diagnose (ICD-10). Interventionen: pharmakogenetisches Screening und integrierte Versorgung; integrierte Versorgung; Standardversorgung. Die Erhebung des medizinischen Nutzens erfolgt durch Messung des klinischen Outcome bzgl. der patientenrelevanten Endpunkte Mortalität, Morbidität, Lebensqualität und Nebenwirkungen zu definierten Zeitpunkten. Perspektivisch relevante Kosten werden im "piggy back"-Verfahren ermittelt. Ergebnisse: Angesichts zurzeit bestehender Limitationen im deutschen Gesundheitssystem (z.B. unzureichendes intersektorales Schnittstellenmanagement bei der Arzneimittelversorgung und Informationsweitergabe) wird die Integrierte Versorgung als geeignete Versorgungsform für den Nutzennachweis eingestuft. Die Integrierte Versorgung stellt jedoch momentan nicht den allgemeinen Standard der psychiatrischen Patientenversorgung dar. Aus GKV-Perspektive wesentliche Kostentreiber der Schizophrenietherapie sind Rückfälle, Krankenhausaufenthalte, Arbeitslosigkeit und vorzeitige Verrentung. Eine Verringerung der Häufigkeit dieser Parameter könnte z.B. zu einer Reduktion der Erstjahres-Behandlungskosten (zurzeit ca. 30% der Gesamtkosten) führen. Die Kosten-Effektivitäts-Analyse erweist sich als Studienform mit der geringsten Anfälligkeit für Bias und Confounder. Trotz einer vergleichsweise hohen externen Validität ist das Studiensetting nicht uneingeschränkt übertragbar auf die Versorgungsrealität des deutschen Gesundheitssystems. Es existiert aktuell keine generelle Empfehlung für den Einsatz der Gendiagnostik zur Steuerung der Arzneimitteltherapie in Psychiatrie. Ebenso hat die integrierte Versorgung bisher keinen umfassenden Einzug in den psychiatrischen Behandlungsalltag gefunden, so dass die beschriebenen Limitationen einen positiven Nutzennachweis erschweren. Dennoch ist das Konzept als praktisch umsetzbar zu bewerten. Schlussfolgerung: Bei dieser Faktenlage ist das Interesse der GKV an der Veranlassung einer gesundheitsökonomischen Evaluation mit dem Ziel einer Erstattungsfähigkeit des a priori durchgeführten pharmakogenetischen Screenings bei Schizophrenie als eher gering einzustufen. Jedoch lassen das Update der S3-Praxisleitlinie mit dem Einbezug der strukturierten u. integrierten Versorgung sowie der Aktionsplan „Individualisierte Medizin“ des Bundesforschungsministeriums auf eine Fokussierung auf diese Fragestellung und veränderte Interessenlage bzgl. der Initiierung der Pilotstudie hoffen. Weitere Forschungstätigkeit sowie die praktische Erprobung neuer gendiagnostischen Verfahren sind, basierend auf versorgungsbezogenen Pilotstudien wie der hier konzeptionierten, fachübergreifend erforderlich, um die Relevanz der Methodik für den psychiatrischen Versorgungsalltag zu belegen. / Purpose: Development of a health-economic investigation method to study whether a cost reduction under concurrent optimisation of the medical use exists by using pharmacogenetic a- priori- screening with first diagnosis of a schizophrenia. Final objective is the reimbursement of pharmacogenetic diagnostics for the indication schizophrenia in the German health statutory insurance (GKV). Methods: A prospective, randomised and controlled, 3-armed, parallel, open, multicentre pilot study with a duration of 3 years was designed based on the actual status of genetic-diagnostic research as well as the evidence-based therapy of schizophrenia. Study population: 300 patients (1:1:1) aged 18 to 65 years with initial F20 diagnosis (ICD-10). Interventions: pharmacogenetic screening and integrated care; integrated care; standard care. For evaluation of the medical benefit the clinical outcome is measured at defined times with regard to the patients' relevant endpoints mortality, morbidity, quality of life and side effects. In perspective relevant costs are determined by "piggy back" procedure. Results: In view of actually existing limitations within the German health system (e.g., insufficient intersectional medication and information management) the integrated care is considered being a suitable setting to demonstrate the advantage of using pharmacogenetic screening. Nevertheless, the integrated care does not show the general standard of the psychiatric patient's care at the moment. From GKV perspective essential cost drivers of schizophrenia therapy are relapses, hospital stays, unemployment and untimely superannuation. Diminishing the rate of these parametres could lead, e.g., to a reduction of the first year medical costs (at the moment approx. 30% of the total expenses). The cost-effectiveness analysis seems to be the study form with the slightest susceptibility to bias and confounding. In spite of a relatively high external validity the study setting is not unconditionally transferable to the German health system. Currently no general recommendation exists for the application of the genetic diagnostics to manage medication therapy in psychiatry. Up to now also the integrated care has not found a comprehensive entry in psychiatric practice, so that the described limitations are complicating a positive use proof. Nevertheless, the investigational concept can be regarded as feasible. Conclusion: Based on the existing situation the GKV's interest in performing a health-economic evaluation, which is focussed on the reimbursement of pharmacogenetic a priori-diagnostics in schizophrenia, is considered to be low. However, the situation may change in view of the expected update of the S3-practise guideline with the focus on structured and integrated care as well as the action plan „individualised medicine“ of the German federal research ministry. Thus, there is hope for changing interests in a pilot study. Based on care-related pilot studies as presented here, further research activities and practical testing of recent gene diagnostic procedures are necessary to demonstrate the relevance of the methodology for psychiatric practice.

No description available.

HINTERGRUND UND ZIELE: Es ist allgemein anerkannt, dass neben Umweltfaktoren auch erbliche Faktoren in hohem Maße für interindividuelle Unterschiede in der Wirkweise von Arzneimitteln ursächlich sind. Die Spannweite der Arzneimittelwirkung bei gleicher Dosis kann individuell von Therapieversagen bis hin zu toxischer Überdosierung reichen und ist dabei stark von Arzneimittel-metabolisierenden Enzymen und Transportern beeinflusst. Genetische Varianten können teilweise interindividuelle Unterschiede in der Aktivität dieser Enzyme und Transporter erklären. Es bleibt jedoch unbekannt, wie viel der Variation in der Aktivität durch Erblichkeit bedingt ist und nicht durch bereits bekannte genetische Varianten erklärt werden kann. Primäres Ziel der Studie war es, diesen unbekannten erblichen Anteil in der Variation der Aktivität der Enzyme CY2D6 und CYP2C9 sowie des Transporters OATP1B1 zu quantifizieren. METHODEN: Die Erblichkeit in der Variation der Aktivität von CY2D6, CYP2C9 und OATP1B1 wurde in 20 mono- und 9 dizygoten, gleichgeschlechtlichen Zwillingspaaren untersucht. Die Testsubstanzen Metoprolol (CYP2D6) und Torasemid (CYP2C9 und OATP1B1) wurden jedem Studienteilnehmer wiederholt verabreicht und die Fläche unter der Kurve bis unendlich (AUC0-inf) für jedes Medikament und seinen Metaboliten als Marker der Enzym- (CYP2D6, CYP2C9) und Transporter- (OATP1B1) Aktivitäten bestimmt. Erblichkeit wurde mithilfe von Formeln mit den Korrelationskoeffizienten der Geschwister in den Gruppen mono- und dizygote Zwillingspaare, durch eine Strukturgleichungsmodellierung und durch Vergleich der intra- und interindividuellen Variation berechnet. ERGEBNISSE: Es wurde ein hohe Erblichkeit in der Variation der Aktivität von CYP2D6, CYP2C9 und OATP1B1 berechnet. Für CYP2D6 lag die Erblichkeit bei 88,5% -100%, für CYP2C9 und OATP1B1 bei 81% - 100%. Die bekannten genetischen Varianten konnten lediglich einen geringen Anteil der Variation in der AUC0-inf in der Studienpopulation erklären (38,2% durch genetische Varianten in CYP2D6, 6,5% durch genetische Varianten in CYP2C9 und 20,4% durch genetische Varianten in OATP1B1). FAZIT: Die Berechnungen zeigen, dass Erblichkeit einen großen Einfluss auf die Variation in der Aktivität der Enzyme CYP2D6, CYP2C9 und den Transporter OATP1B1 hat. Bekannte genetische Varianten können hiervon nur einen Teil erklären. Weitere Untersuchungen zu genetischen Regulation der Wirkweise von Arzneimitteln erscheinen vielversprechend.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser + 1 appendix.