The HUGO Journal

The concept of personalized medicine not only promises to enhance the life of patients and increase the quality of clinical practice and targeted care pathways, but also to lower overall healthcare costs through early-detection, prevention, accurate risk assessments and efficiencies in care delivery. Current inefficiencies are widely regarded as substantial enough to have a significant impact on the economies of major nations like the US and China, and, therefore the world economy. A recent OECD report estimates healthcare expenditure for some of the developed western and eastern nations to be anywhere from 10% to 18%, and growing (with the US at the highest). Personalized medicine aims to use state-of-the-art genomic technologies, rich medical record data, tissue and blood banks and clinical knowledge that will allow clinicians and payors to tailor treatments to individuals, thereby greatly reducing the costs of ineffective therapies incurred through the current trial and error clinical paradigm. Pivotal to the field are drugs that have been designed to target a specific molecular pathway that has gone wrong and results in a diseased condition and the diagnostic tests that allow clinicians to separate responders from non-responders. However, the truly personalized approach in medicine faces two major problems: complex biology and complex economics; the pathways involved in diseases are quite often not well understood, and most targeted drugs are very expensive. As a result of all current efforts to translate the concepts of personalized healthcare into the clinic, personalized medicine becomes participatory and this implies patient decisions about their own health. Such a new paradigm requires powerful tools to handle significant amounts of personal information with the approach to be known as “P4 medicine”, that is predictive, preventive, personalized and participatory. P4 medicine promises to increase the quality of clinical care and treatments and will ultimately save costs. The greatest challenges are economic, not scientific.

Scientific and technological advances derived from the genomics revolution have a central role to play in dealing with continuing infectious disease threats in the developing world caused by emerging and re-emerging pathogens. These techniques, coupled with increasing knowledge of host-pathogen interactions, can assist in the early identification and containment of outbreaks as well as in the development of preventive vaccination and therapeutic interventions, including the urgent need for new antibiotics. However, the effective application of genomics technologies faces key barriers and challenges which occur at three stages: from the research to the products, from the products to individual patients, and, finally, from patients to entire populations. There needs to be an emphasis on research in areas of greatest need, in facilitating the translation of research into interventions and, finally, the effective delivery of such interventions to those in greatest need. Ultimate success will depend on bringing together science, society and policy to develop effective public health implementation strategies to provide health security and health equity for all peoples.

This paper explores young people’s attitudes to genetics. It describes a qualitative study involving a group of teenagers in a deprived South Wales valley town over a period of 18 months. The GAMY (Genetics and Merthyr Youth) Project involved a series of interactions with participants, including 2 interviews, 4 group days and 4 genetics tasks through which these young people learned about, and then reflected upon, issues relating to genetics and health. We have gathered data about the informed attitudes of teenagers to genetics based on deliberative learning and reflection over a long period of time, and as such this paper provides useful insights into the underlying values that are guiding young people’s views and the factors that are shaping their responses to new genetic technologies. Attitudes to genetics are complex and not easily generalisable. There were low levels of familiarity with, and knowledge of, genetics from the outset. Most young people did not have pre-existing attitudes towards genetics and had given little or no thought to the topic before the project began. However, levels of awareness and general genetic literacy increased as the project progressed. This study suggests that over time young people can develop an awareness of genetics that makes sense to them; they demonstrate that they can think creatively about genetics, and they are able to engage in considering genetic and other risk factors when thinking about health and disease.

Massive parallel sequencing has revolutionized the search for pathogenic variants in the human genome, but for routine diagnosis, re-sequencing of the complete human genome in a large cohort of patients is still far too expensive. Recently, novel genome partitioning methods have been developed that allow to target re-sequencing to specific genomic compartments, but practical experience with these methods is still limited. In this study, we have combined a novel droplet-based multiplex PCR method and next generation sequencing to screen patients with X-linked mental retardation (XLMR) for mutations in 86 previously identified XLMR genes. In total, affected males from 24 large XLMR families were analyzed, including three in whom the mutations were already known. Amplicons corresponding to functionally relevant regions of these genes were sequenced on an Illumina/Solexa Genome Analyzer II platform. Highly specific and uniform enrichment was achieved: on average, 67.9% unambiguously mapped reads were derived from amplicons, and for 88.5% of the targeted bases, the sequencing depth was sufficient to reliably detect variations. Potentially disease-causing sequence variants were identified in 10 out of 24 patients, including the three mutations that were already known, and all of these could be confirmed by Sanger sequencing. The robust performance of this approach demonstrates the general utility of droplet-based multiplex PCR for parallel mutation screening in hundreds of genes, which is a prerequisite for the diagnosis of mental retardation and other disorders that may be due to defects of a wide variety of genes.

Angiotensin-I-converting enzyme (ACE) is known to be associated with human cardiovascular and psychiatric pathophysiology. We have undertaken a global survey of the haplotypes in ACE gene to study diversity and to draw inferences on the nature of selective forces that may be operating on this gene. We have investigated the haplotype profiles reconstructed using polymorphisms in the regulatory (rs4277405, rs4459609, rs1800764, rs4292, rs4291), exonic (rs4309, rs4331, rs4343), and intronic (rs4340; Alu [I/D]) regions covering 17.8 kb of the ACE gene. We genotyped these polymorphisms in a large number of individuals drawn from 15 Indian ethnic groups and estimated haplotype frequencies. We compared the Indian data with available data from other global populations. Globally, five major haplotypes were observed. High-frequency haplotypes comprising mismatching alleles at the loci considered were seen in all populations. The three most frequent haplotypes among Africans were distinct from the major haplotypes of other world populations. We have studied the evolution of the two major haplotypes (TATATTGIA and CCCTCCADG), one of which contains an Alu insertion (I) and the other a deletion (D), seen most frequently among Caucasians (68%), non-African HapMap populations (65–88%), and Indian populations (70–95%) in detail. The two major haplotypes among Caucasians are reported to represent two distinct clades A and B. Earlier studies have postulated that a third clade C (represented by the haplotypes TACATCADG and TACATCADA) arose from an ancestral recombination event between A and B. We find that a more parsimonious explanation is that clades A and B have arisen by recombination between haplotypes belonging to clade C and a high-frequency African haplotype CCCTTCGIA. The haplotypes, which according to our hypothesis are the putative non-recombinants (PuNR), are uncommon in all non-African populations (frequency range 0–12%). Conversely, the frequencies of the putative recombinant haplotypes (PuR) are very low in the Africans populations (2–8%), indicating that the recombination event is likely to be ancient and arose before, perhaps shortly prior to, the global dispersal of modern humans. The global frequency spectrum of the PuR and the PuNR is difficult to explain only by drift. It appears likely that the ACE gene has been undergoing a combination of different selective pressures.

Multiple lines of evidence suggest regulatory variation to play an important role in phenotypic evolution and disease development, but few regulatory polymorphisms have been characterized genetically and molecularly. Recent technological advances have made it possible to identify bona fide regulatory sequences experimentally on a genome-wide scale and opened the window for the biological interrogation of germ-line polymorphisms within these sequences. In this study, through a forward genetic analysis of bona fide p53 binding sites identified by a genome-wide chromatin immunoprecipitation and sequence analysis, we discovered a SNP (rs1860746) within the motif sequence of a p53 binding site where p53 can function as a regulator of transcription. We found that the minor allele (T) binds p53 poorly and has low transcriptional regulation activity as compared to the major allele (G). Significantly, the homozygosity of the minor allele was found to be associated with an increased risk of ER negative breast cancer (OR = 1.47, P = 0.038) from the analysis of five independent breast cancer samples of European origin consisting of 6,127 breast cancer patients and 5,197 controls. rs1860746 resides in the third intron of the PRKAG2 gene that encodes the γ subunit of the AMPK protein, a major sensor of metabolic stress and a modulator of p53 action. However, this gene does not appear to be regulated by p53 in lymphoblastoid cell lines nor in a cancer cell line. These results suggest that either the rs1860746 locus regulates another gene through distant interactions, or that this locus is in linkage disequilibrium with a second causal mutation. This study shows the feasibility of using genomic scale molecular data to uncover disease associated SNPs, but underscores the complexity of determining the function of regulatory variants in human populations.