Incidental genetic findings in randomized clinical trials: recommendations from the Genomics and Randomized Trials Network (GARNET)

Genome-wide polygenic risk score for major osteoporotic fractures in postmenopausal women using associated single nucleotide polymorphisms

BACKGROUND

Osteoporosis is highly polygenic and heritable, with heritability ranging from 50 to 80%; most inherited susceptibility is associated with the cumulative effect of many common genetic variants. However, existing genetic risk scores (GRS) only provide a few percent predictive power for osteoporotic fracture.

METHODS

We derived and validated a novel genome-wide polygenic score (GPS) comprised of 103,155 common genetic variants to quantify this susceptibility and tested this GPS prediction ability in an independent dataset (n = 15,776).

RESULTS

Among postmenopausal women, we found a fivefold gradient in the risk of major osteoporotic fracture (MOF) (p < 0.001) and a 15.25-fold increased risk of severe osteoporosis (p < 0.001) across the GPS deciles. Compared with the remainder of the GPS distribution, the top GPS decile was associated with a 3.59-, 2.48-, 1.92-, and 1.58-fold increased risk of any fracture, MOF, hip fracture, and spine fracture, respectively. The top GPS decile also identified nearly twofold more high-risk osteoporotic patients than the top decile of conventional GRS based on 1103 conditionally independent genome-wide significant SNPs. Although the relative risk of severe osteoporosis for postmenopausal women at around 50 is relatively similar, the cumulative incident at 20-year follow-up is significantly different between the top GPS decile (13.7%) and the bottom decile (< 1%). In the subgroup analysis, the GPS transferability in non-Hispanic White is better than in other racial/ethnic groups.

CONCLUSIONS

This new method to quantify inherited susceptibility to osteoporosis and osteoporotic fracture affords new opportunities for clinical prevention and risk assessment.

Moral Duties of Genomics Researchers: Why Personalized Medicine Requires a Collective Approach

Advances in genome sequencing together with the introduction of personalized medicine offer promising new avenues for research and precision treatment, particularly in the field of oncology. At the same time, the convergence of genomics, bioinformatics, and the collection of human tissues and patient data creates novel moral duties for researchers. After all, unprecedented amounts of potentially sensitive information are being generated. Over time, traditional research ethics principles aimed at protecting individual participants have become supplemented with social obligations related to the interests of society and the research enterprise at large, illustrating that genomic medicine is also a social endeavor. In this review we provide a comprehensive assembly of moral duties that have been attributed to genomics researchers and offer suggestions for responsible advancement of personalized genomic cancer care.

Obesity and associated lifestyles modify the effect of glucose metabolism-related genetic variants on impaired glucose homeostasis among postmenopausal women

PURPOSE

Impaired glucose metabolism-related genetic variants likely interact with obesity-modifiable factors in response to glucose intolerance, yet their interconnected pathways have not been fully characterized.

METHODS

With data from 1,027 postmenopausal participants of the Genomics and Randomized Trials Network study and 15 single-nucleotide polymorphisms (SNPs) associated with glucose homeostasis, we assessed whether obesity, physical activity, and high dietary fat intake interact with the SNP-glucose variations. We used regression analysis plus stratification and graphic approaches.

RESULTS

Across carriers of the 15 SNPs, fasting levels of glucose, insulin, and homeostatic model assessment-insulin resistance (HOMA-IR) were higher in obese, inactive, and high fat-diet women than in their respective counterparts. Carriers within subgroups differently demonstrated the direction and/or magnitude of the variants' effect on glucose-relevant traits. Variants in GCKR, GCK, DGKB/TMEM195 (P for interactions = 0.02, 0.02, and 0.01), especially, showed interactions with obesity: obese, inactive, and high fat-diet women had greater increases in fasting glucose, insulin, and HOMA-IR levels. Obese carriers at TCF7L2 variant had greater increases in fasting glucose levels than nonobese carriers (P for interaction = 0.04), whereas active women had greater decreases in insulin and HOMA-IR levels than inactive women (P for interaction = 0.02 in both levels).

CONCLUSIONS

Our data support the important role of obesity in modifying glucose homeostasis in response to glucose metabolism-relevant variants. These findings may inform research on the role of glucose homeostasis in the etiology of chronic disease and the development of intervention strategies to reduce risk in postmenopausal women.

Tumor profiling and the incidentalome: patient decisions and risks

In recent years, the field of oncology has witnessed rapid advancements in genetic sequencing simultaneously with steeply declining costs of sequencing technology. As a result, genomics-driven cancer medicine and the use of tumor profiling are quickly becoming mainstays of cancer therapy. Oncology patients can benefit from tumor profiling by allowing the selection of targeted therapies tailored to their disease. However, it is increasingly recognized that the process of determining a tumor DNA sequence may lead to incidental discovery of underlying germline mutations which can impact other aspects of a patient’s health, and that of their family. How to handle the ‘incidentalome’ has been the subject of recent public debate, yet patient education about the potential risks of tumor profiling remains sparse. Patient perspectives and clinical implications of the tumor incidentalome must be specifically addressed by the oncology community as tumor profiling expands to become a new standard of care.

Shared responsibility for ensuring appropriate management of incidental findings: a case study from South Africa

We report the case of an HIV prevention clinical trial participant who was referred to a local hospital for investigation and management of an incidental finding unrelated to her study participation. This case illustrates the complexities in the management of incidental findings within the context of clinical trials and highlights the importance of ethical oversight of trials.

TRIAL REGISTRATION NUMBER

Protocol number ISRCTN64716212.

Return of Genetic Research Results to Participants and Families: IRB Perspectives and Roles

We surveyed IRB chairs' perspectives on offering individual genetic research results to participants and families, including family members of deceased participants, and the IRB's role in addressing these issues. Given a particular hypothetical scenario, respondents favored offering results to participants but not family members, giving choices at the time of initial consent, and honoring elicited choices. They felt IRBs should have authority regarding the process issues, but a more limited role in medical and scientific issues.

Models of consent to return of incidental findings in genomic research

Genomic research-including whole genome sequencing and whole exome sequencing-has a growing presence in contemporary biomedical investigation. The capacity of sequencing techniques to generate results that go beyond the primary aims of the research-historically referred to as "incidental findings"-has generated considerable discussion as to how this information should be handled-that is, whether incidental results should be returned, and if so, which ones.Federal regulations governing most human subjects research in the United States require the disclosure of "the procedures to be followed" in the research as part of the informed consent process. It seems reasonable to assume-and indeed, many commentators have concluded-that genomic investigators will be expected to inform participants about, among other procedures, the prospect that incidental findings will become available and the mechanisms for dealing with them. Investigators, most of whom will not have dealt with these issues before, will face considerable challenges in framing meaningful disclosures for research participants.To help in this task, we undertook to identify the elements that should be included in the informed consent process related to incidental findings. We did this by surveying a large number of genomic researchers (n = 241) and by conducting in-depth interviews with a smaller number of researchers (n = 28) and genomic research participants (n = 20). Based on these findings, it seems clear to us that routine approaches to informed consent are not likely to be effective in genomic research in which the prospect of incidental findings exists. Ensuring that participants' decisions are informed and meaningful will require innovative approaches to dealing with the consent issue. We have identified four prototypical models of a consent process for return of incidental findings.

Informed consent for return of incidental findings in genomic research

PURPOSE

Researchers face the dilemma of how to obtain consent for return of incidental findings from genomic research. We surveyed and interviewed investigators and study participants, with the goal of providing suggestions for how to shape the consent process.

METHODS

We performed an online survey of 254 US genetic researchers identified through the NIH RePORTER database, abstracts from the 2011 American Society of Human Genetics meeting, and qualitative semi-structured interviews with 28 genomic researchers and 20 research participants.

RESULTS

Most researchers and participants endorsed disclosure of a wide range of information about return of incidental findings, including risks, benefits, impact on family members, data security, and procedures, for return of results in the event of death or incapacity and for recontact. However, most researchers were willing to devote 30 min or less to this process and expressed concerns that disclosed information would overwhelm participants, a concern shared by many participants themselves.

CONCLUSION

There is a disjunction between the views of investigators and participants about the amount of information that should be disclosed and the practical realities of the research setting, including the time available for consent discussions. This strongly suggests the need for innovative approaches to the informed consent process.