| Literature DB >> 22818218 |
Abstract
BACKGROUND: The revolution in DNA sequencing technologies over the past decade has made it feasible to sequence an individual's whole genome at a relatively low cost. The potential value of the information generated by genomic technologies for medicine and society is enormous. However, in order for exome sequencing, and eventually whole genome sequencing, to be implemented clinically, a number of major challenges need to be overcome. For instance, obtaining meaningful informed-consent, managing incidental findings and the great volume of data generated (including multiple findings with uncertain clinical significance), re-interpreting the genomic data and providing additional counselling to patients as genetic knowledge evolves are issues that need to be addressed. It appears that medical genetics is shifting from the present "phenotype-first" medical model to a "data-first" model which leads to multiple complexities. DISCUSSION: This manuscript discusses the different challenges associated with integrating genomic technologies into clinical practice and describes a "phenotype-first" approach, namely, "Individualized Mutation-weighed Phenotype Search", and its benefits. The proposed approach allows for a more efficient prioritization of the genes to be tested in a clinical lab based on both the patient's phenotype and his/her entire genomic data. It simplifies "informed-consent" for clinical use of genomic technologies and helps to protect the patient's autonomy and privacy. Overall, this approach could potentially render widespread use of genomic technologies, in the immediate future, practical, ethical and clinically useful.Entities:
Mesh:
Year: 2012 PMID: 22818218 PMCID: PMC3439266 DOI: 10.1186/1755-8794-5-31
Source DB: PubMed Journal: BMC Med Genomics ISSN: 1755-8794 Impact factor: 3.063
Challenges of integrating ES/WGS in clinical practice
Figure 1Schematic overview of I-MPOS, the new clinical genetic approach proposed. Patients have their exome/genome sequenced and their encrypted data stored on a password-protected platform which remains at the disposal of the individual patient. A patient presents to clinic with a specific medical concern. The physician performs a clinical evaluation and identifies some important features (“phenotype-first” approach). He or she then performs a database search using keywords related to the clinically assessed phenotype, as presently done, thereby providing an initial ranking of possible genetic diseases. This initial ranking is then adjusted by I-MPOSE based on the weight scores automatically assigned to the mutations identified by ES/WGS in the patient’s genes/loci known to be linked to each genetic disease; thus providing a second ranking of the possible genetic diseases. I-MPOSE simultaneously operates on the patient’s encrypted data and on a regularly updated database containing all well characterized genetic diagnoses. It is run during every clinical visit so as to incorporate new findings from clinical evaluation, as well as, new genetic knowledge incorporated in the regularly updated database.
Figure 2Examples of factors to be taken into consideration when calculating a variant’s “weight”. An overall score is automatically calculated by I-MPOSE for each variant identified with ES/WGS by simultaneously taking into consideration different factors. Some examples of such factors are listed above in Figure. 2. Information about the pattern of inheritance can also be factored in the weight assignment process (Figure.2b). The overall score corresponds to the level of certainty for the pathogenicity of each genetic variant identified. An option to allow for adjusting the default parameters is possible through an interactive checklist. The physician can opt to assign a different contribution for a specific parameter (e.g. a much increased contribution for homozygosity when dealing with consanguinity) in the calculation of the variant’s overall score.
Figure 3Examples of ongoing projects & tools illustrating that the necessary infrastructure for I-MPOSE is already available. Some examples of existing databases for human disease and genetic variation, as well as, tools available for the annotation of variants identified by ES/WGS.
Benefits of the I-MPOS approach
| -Simplification of pre-test counselling, informed consent and post-test counselling | |
| -Protection of the patient’s privacy and autonomy | |
| -Genomic sequencing, even during newborn period, practical, ethical and clinically useful | |
| -Increased diagnostic yield; cost-effective approach; decreased time to diagnosis | |
| -Overcomes challenges such as shortage of personnel, the management of the huge amount of data generated, incidental findings, VUS, and duty to re-contact. | |
| -Incremental integration of genomic technologies into clinical practice. | |
| -Standardized approach in medical genomics, even where resources are limited | |
| -Promotion of genomic research | |
| -Refinement of clinical phenotype: partial matches for known syndromes; biochemical phenotypes | |
| -Prevents over-medicalization of genomic data while enabling serving the patient’s concerns | |
| -Progressive education of both the health care personnel and the general public regarding personalized/preventive medicine |