Genetic determinants of response to aspirin and warfarin and development of silicon nanowire based genotyping

PhD ThesisChronic diseases such as cardiovascular diseases and colorectal cancer are the leading cause of mortality worldwide. Commonly used drugs such as aspirin and warfarin are shown to effective at reducing the risk of chronic diseases but have a narrow therapeutic window and are associated with adverse drug reactions, particularly, hemorrhage. Identification of pharmacogenetic markers such as single nucleotide polymorphisms (SNPs) that could help deliver personalized dose could help improve the risk-benefit ratio. Furthermore, development of a rapid point of care genotyping device consisting of a pharmacogenetic SNP panel for aspirin and warfarin could help implement personalized medicine in the clinical setting. Analysis of candidate SNPs in aspirin’s pharmacokinetic and pharmacodynamic pathways was carried out to explain variation in aspirin’s colorectal chemopreventive efficacy using two large population based case-control datasets. Associations and interactions were tested using logistic regression models and meta-analysis of the 2 datasets. A novel sitespecific association for rs1799853 (OR=0.73, 95% CI=0.60-0.90, P=0.003) and rs1105879 (OR=1.16, 95% CI=1.02-1.32, P=0.03) with colon cancer risk was observed. Furthermore, stratification by aspirin use showed increased risk of colorectal cancer in aspirin users but not in non-users carrying variant allele of the SNPs rs4936367 and rs7112513 in PAFAH1B2 gene and rs2070959 and rs1105879 in UGT1A6 gene (Pinteraction<0.05 for all). These results provide insight into aspirin’s differential chemopreventive efficacy and the neoplastic transformation of cells in colon and rectum. Utility of clinically validated pharmacogenetic dosing algorithms consisting of three warfarin dose associated SNPs from the European population needs to tested in the Gujarati Indians, an Indian sub-population. Dose prediction accuracy of the algorithms was compared between Gujarati Indian and European population. Mean squared difference of both pharmacogenetic algorithms was higher in Gujarati Indian compared to European population (Klein et al 2009, 216.3 v/s 160.7, P=0.05; Gage et al 2008, 170.6 v/s 143.2, P=0.07). Poor prediction accuracy could be explained by the presence of study subjects requiring dose for target INR range 2.5-3.5 and low frequency of the VKORC1 rs9923231 variant, which is the most important genetic determinant of warfarin dosing in Europeans. Therefore, the SNP panel and dosing algorithms developed from European populations cannot be assumed to have utility in the Gujarati Indian population. Finally, to help develop a rapid, point-of care, silicon nanowire (SiNW) based SNP genotyping device, a panel of isothermal melting probes were designed to genotype three warfarin dose associated SNPs. Testing of hybridization and washing conditions to have optimal hybridization kinetics between the probe and target DNA and high target sequence specificity was carried out using custom designed microarray platform. Accurate genotype calls for all 3 SNPs in 2 anonymised samples using empirically optimized hybridization and washing conditions was carried out successfully. Current work highlighted associations between probe characteristics and hybridization parameters, which would be useful in designing and testing probes on the SiNW platform. Identification, validation and testing of clinical utility of population specific pharmacogenetic markers along with development and deployment of ultra-rapid point of care genotyping technologies could help deliver personalized risk-benefit ratio for aspirin and warfarin

A small supernumerary marker chromosome present in a Turner syndrome patient not derived from X- or Y-chromosome: a case report

<p>Abstract</p> <p>Background</p> <p>Small supernumerary marker chromosomes (sSMC) can be present in numerically abnormal karyotypes like in a 'Turner-syndrome karyotype' mos 45,X/46,X,+mar.</p> <p>Results</p> <p>Here we report the first case of an sSMC found in Turner syndrome karyotypes (sSMC^T) derived from chromosome 14 in a Turner syndrome patient. According to cytogenetic and molecular cytogenetic characterization the karyotype was 46,X,+del(14)(q11.1). The present case is the third Turner syndrome case with an sSMC^Tnot derived from the X- or the Y-chromosome.</p> <p>Conclusion</p> <p>More comprehensive characterization of such sSMC^Tmight identify them to be more frequent than only ~0.6% in Turner syndrome cases according to available data.</p

Natural history of non-lethal raine syndrome during childhood

Background: Raine syndrome (RS) is a rare autosomal recessive disorder caused by biallelic loss-of-function mutations of FAM20C. The most common clinical features are microcephaly, exophthalmos, hypoplastic nose and severe midface hypoplasia, leading to choanal atresia. The radiological findings include generalized osteosclerosis and brain calcifications. RS is usually lethal during the neonatal period due to severe respiratory distress. However, there exists a non-lethal RS form, the phenotype of which is extremely heterogeneous. There is paucity of data about clinical course and life expectancy of these patients.Results: This is the first description of follow-up features of non-lethal RS patients. Moreover, we present three unpublished cases. There are five Asian and two Arab patients. All were born to consanguineous parents. The most common neonatal comorbidity was respiratory distress secondary to choanal atresia. A variable degree of neurodevelopmental delay was seen in the majority of our cases and seizures and hearing or vision involvement were also frequent. Neurological and orthopedic issues were the most frequent complications seen at follow-up in our group. Persistent hypophosphatemic rickets was the most striking endocrinological manifestation, which was scarcely responsive to therapy with phosphate salts and alfacalcidol. Life expectancy of our patients goes beyond childhood, with the oldest of those described being 18 years old at present.Conclusions: Manifestations of RS in those surviving the neonatal period are being increasingly recognized. Our study supports previous findings and provides clinical and biochemical observations and data from longer follow up. Finally, we propose multidisciplinary follow up for patients with non-lethal RS

Designing a Do It Yourself (DIY) toolkit to enable dispersed corporate entrepreneurship

As businesses mature over time, companies need to find and invest in new growth opportunities. However, finding growth opportunities through innovation is difficult for well-established companies. They are better at execution than innoavtion, and most of them succeed by optimising their existing businesses rather than through creativity and innovations. Elisa Oyj is one such company in Finland, and the case organisation for the thesis. The purpose of this thesis is to help Elisa generate new service innovations by creating a do-it-yourself toolkit and its governance model that would enable dispersed corporate entrepreneurship in the company. The aim of the toolkit is to help employees test if their ideas have business potential or not. The aim of the governance model is to help the managers manage such a bottom-up innovation effort. Taking into consideration the complexity of the development project, the thesis first sheds light on the need for corporate innovation, the economics of innovation, the theories on how corporates could innovate based on the presence of a particular long-wave economic cycle and the current approach in corporate innovation and its management. Since the focus of the case organisation is on coming up with service innovations, the thesis also explores the role of service dominant logic as a theoretical base in coming up with service innovations and utilises human centred design and lean startup as two approaches to bring new service innovations to market. SDL aligns very well with Elisa in practice, because the company’s management believes that no business can exist if it does not solve a customer problem. To create the contents for the toolkit and its governance model, a service design process based on the double diamond method was adopted. Qualitative research, including interviews and workshops with Elisa’s employees, decision-makers and innovators from other companies was undertaken. These insights were made actionable through design principles, which offered guidance on the features of the toolkit and its governance model. The results of the are presented through the iterations of the toolkit and its governance model, which offer an understanding of the content and the desired innovation process both for the employee who might use the toolkit as well as management who will manage it in the future. This thesis has both scientific and practical value. The scientific value of the study comes from the results of the thesis being commensurate with literature on corporate entrepreneurship, its management, service dominant logic and new service development process. The practical value of the thesis stems from the process used in designing the toolkit, its contents and its governance model, and the considerations and analysis undertaken while designing its contents. This might help other companies create such toolkits and processes to promote entrepreneurship in their companies. As of now, Idea box will be piloted in software services business unit in Elisa, with the possibility to scale across Elisa in the future