Attitudes, Knowledge, and Risk Perceptions of Patients who Received Elective Genomic Testing as a Clinical Service.

BACKGROUND: Elective genomic testing (EGT) is increasingly available clinically. Limited real world evidence exists about attitudes and knowledge of EGT recipients. METHODS: After web-based education, patients who enrolled in an EGT program at a rural nonprofit healthcare system completed a survey that assessed attitudes, knowledge, and risk perceptions. RESULTS: From August 2020 to April 2022, 5,920 patients completed the survey and received testing. Patients most frequently cited interest in learning their personal disease risks as their primary motivation. Patients most often expected results to guide medication management (74.0%), prevent future disease (70.4%), and provide information about risks to offspring (65.4%). Patients were "very concerned" most frequently about the privacy of genetic information (19.8%) and how well testing predicted disease risks (18.0%). On average, patients answered 6.7 of 11 knowledge items correctly (61.3%). They more often rated their risks for colon and breast cancers as lower rather than higher than the average person, but more often rated their risk for a heart attack as higher rather than lower than the average person (all p<0.001). CONCLUSION: Patients pursued EGT because of the utility expectations, but often misunderstood the test's capabilities.

The Potential of Genetics in Identifying Women at Lower Risk of Breast Cancer.

Importance: Genetic information is not being used to identify women at lower risk of breast cancer or other diseases in clinical practice. With the new US Preventive Services Task Force guidelines lowering the age for mammogram screening for all, there is a potential benefit in identifying women at lower risk of disease who may defer the start of mammographic screening. This genetic risk-based approach would help mitigate overscreening, associated costs, and anxiety. Objective: To assess breast cancer incidence and age of onset among women at low genetic risk compared with women at average risk and evaluate the potential to delay mammography on the basis of genetic risk stratification. Design, Setting, and Participants: This retrospective case-control study included 25 591 women from the Healthy Nevada Project sequenced by Helix between 2018 and 2022. Data extracted from electronic health records at the end of 2022 (mean length of electronic health record available was 12 years) were used for the analysis in 2023. Main Outcomes and Measures: Breast cancer diagnosis was identified from electronic health records. Classification to the low-risk genetic group required (1) the absence of pathogenic variants or a variant of uncertain significance in BRCA1, BRCA2, PALB2, ATM, or CHEK2, and (2) a low polygenic risk score (bottom 10%) using a 313-single-nucleotide variant model. Results: Of 25 591 women in the study (mean [SD] age was 53.8 [16.9] years), 2338 women (9.1%) were classified as having low risk for breast cancer; 410 women (1.6%) were classified as high risk; and 22 843 women (89.3%) as average risk. There was a significant reduction in breast cancer diagnosis among the low-risk group (hazard ratio, 0.39; 95% CI, 0.29-0.52; P < .001). By 45 years of age, 0.69% of women in the average-risk group were diagnosed with breast cancer, whereas women in the low-risk group reached this rate at 51 years. By 50 years of age, 1.41% of those in the average-risk group were diagnosed with breast cancer, whereas those in the low-risk group reached this rate at age 58 years. These findings suggest that deferring mammogram screening by 5 to 10 years for women at low risk of breast cancer aligns with new draft recommendations. Conclusions and Relevance: The findings of this retrospective case-control study underscore the value of genetics in individualizing the onset of breast cancer screening. Improving breast cancer risk stratification by implementing both high-risk and low-risk strategies in screening can refine preventive measures and optimize health care resource allocation.

SLCO1B1 gene-based clinical decision support reduces statin-associated muscle symptoms risk with simvastatin.

Background: SLCO1B1 variants are known to be a strong predictor of statin-associated muscle symptoms (SAMS) risk with simvastatin. Methods: The authors conducted a retrospective chart review on 20,341 patients who had SLCO1B1 genotyping to quantify the uptake of clinical decision support (CDS) for genetic variants known to impact SAMS risk. Results: A total of 182 patients had 417 CDS alerts generated, and 150 of these patients (82.4%) received pharmacotherapy that did not increase risks for SAMS. Providers were more likely to cancel simvastatin orders in response to CDS alerts if genotyping had been done prior to the first simvastatin prescription than after (94.1% vs 28.5%, respectively; p < 0.001). Conclusion: CDS significantly reduces simvastatin prescribing at doses associated with SAMS.

Pharmacogenetic Review: Germline Genetic Variants Possessing Increased Cancer Risk With Clinically Actionable Therapeutic Relationships.

As our understanding of genomics and genetic testing continues to advance, the personalization of medical decision making is progressing simultaneously. By carefully crafting medical care to fit the specific needs of the individual, patients can experience better long-term outcomes, reduced toxicities, and improved healthcare experiences. Genetic tests are frequently ordered to help diagnose a clinical presentation and even to guide surveillance. Through persistent investigation, studies have begun to delineate further therapeutic implications based upon unique relationships with genetic variants. In this review, a pre-emptive approach is taken to understand the existing evidence of relationships between specific genetic variants and available therapies. The review revealed an array of diverse relationships, ranging from well-documented clinical approaches to investigative findings with potential for future application. Therapeutic agents identified in the study ranged from highly specific targeted therapies to agents possessing similar risk factors as a genetic variant. Working in conjunction with national standardized treatment approaches, it is critical that physicians appropriately consider these relationships when developing personalized treatment plans for their patients.

SLCO1B1*5 Allele Is Associated With Atorvastatin Discontinuation and Adverse Muscle Symptoms in the Context of Routine Care.

The SLCO1B1 genotype is known to influence patient adherence to statin therapy, in part by increasing the risk for statin-associated musculoskeletal symptoms (SAMSs). The SLCO1B1*5 allele has previously been associated with simvastatin discontinuation and SAMSs. Prior analyses of the relationship between SLCO1B1*5 and atorvastatin muscle side effects have been inconclusive due to insufficient power. We now quantify the impact of SLCO1B1*5 on atorvastatin discontinuation and SAMSs in a large observational cohort using electronic medical record data from a single health care system. In our study cohort (n = 1,627 patients exposed to atorvastatin during the course of routine clinical care), 56% (n = 912 of 1,627 patients) discontinued atorvastatin and 18% (n = 303 of 1,627 patients) developed SAMSs. A univariate model revealed that SLCO1B1*5 increased the likelihood that patients would stop atorvastatin during routine care (odds ratio 1.2; 95% confidence interval (CI), 1.1-1.5; P = 0.04). A multivariate Cox proportional hazards model further demonstrated that this same variant was associated with time to atorvastatin discontinuation (hazard ratio 1.2; 95% CI, 1.1-1.4; P = 0.004). Additional time-to-event analyses also revealed that SCLO1B1*5 was associated with SAMSs (hazard ratio 1.4; 95% CI, 1.1-1.7; P = 0.02). Atorvastatin discontinuation was associated with SAMSs (odds ratio 1.67; P = 0.0001) in our cohort.

CYP2C19 genotype-directed P2Y12 inhibitor antiplatelet therapy normalizes risk for major adverse cardiovascular events after percutaneous coronary intervention.

OBJECTIVE: To study the use of CYP2C19 genotyping to guide P2Y12 inhibitor selection to maximize efficacy, and attenuate risk in appropriate patients who underwent PCI for CAD. METHODS: We performed a retrospective analysis of 868 patients with CAD who received CYP2C19 genotyping after PCI and changed P2Y12 inhibitor based on the results. Patients were divided into two groups based on clopidogrel metabolizer status. Group I: Intermediate (IM) and poor metabolizers (PM). Group II: Ultra-rapid (UM), rapid (RM) and normal metabolizers (NM). Each group was then categorized to one of two treatment arms guided by CYP2C19 genotype. Category 1: IM/PM started on clopidogrel, switched to ticagrelor or prasugrel; 2:IM/PM started on ticagrelor/prasugrel, continued these medications; 3: UM/RM/NM started on ticagrelor/prasugrel, switched to clopidogrel; 4: UM/RM/NM started on clopidogrel, continued clopidogrel. Death due to cardiac causes, bleeding events, non-fatal MI, target vessel revascularization (TVR), and MACE in all four categories were considered at 1, 6 and 12 months. RESULTS: We did not observe significant difference between phenotypes for MACE at 1 (p = 0.274), 6 (p = 0.387), and 12 months (p = 0.083). Death due to cardiac causes, MI, and bleeding events were not significant at 1, 6, and 12 months. There was no significant difference in TVR at 6 (p = 0.491), and 12 months (p = 0.423) except at 1 month (p = 0.012). CONCLUSION: CYP2C19 genotype-based intervention can be implemented effectively and reliably to guide selection of P2Y12 inhibitor to optimize patient quality and safety when appropriate in post PCI patients.

Primary care providers' responses to unsolicited Lynch syndrome secondary findings of varying clinical significance.

PURPOSE: How primary care providers (PCPs) respond to genomic secondary findings (SFs) of varying clinical significance (pathogenic, uncertain significance [VUS], or benign) is unknown. METHODS: We randomized 148 American Academy of Family Physicians members to review three reports with varying significance for Lynch syndrome. Participants provided open-ended responses about the follow-up they would address and organized the SF reports and five other topics in the order they would prioritize responding to them (1 = highest priority, 6 = lowest priority). RESULTS: PCPs suggested referrals more often for pathogenic variants or VUS than benign variants (72% vs. 16%, p < 0.001). PCPs were also more likely to address further workup, like a colonoscopy or esophagogastroduodenoscopy, in response to pathogenic variants or VUS than benign variants (43% vs. 4%, p < 0.001). The likelihoods of addressing referrals or further workup were similar when PCPs reviewed pathogenic variants and VUS (both p > 0.46). SF reports were prioritized highest for pathogenic variants (2.7 for pathogenic variants, 3.6 for VUS, 4.3 for benign variants, all p ≤ 0.014). CONCLUSION: Results suggest that while PCPs appreciated the differences in clinical significance, disclosure of VUS as SFs would substantially increase downstream health-care utilization.

Expanding the Phenotype of TUBB2A-Related Tubulinopathy: Three Cases of a Novel, Heterozygous TUBB2A Pathogenic Variant p.Gly98Arg.

Tubulinopathies are a group of conditions caused by variants in 6 tubulin genes that present with a spectrum of brain malformations. One of these conditions is TUBB2A-related tubulinopathy. Currently, there are 9 reported individuals with pathogenic variants within the TUBB2A gene, with common manifestations including, but not limited to, global developmental delay, seizures, cortical dysplasia, and dysmorphic corpus callosum. We report 3 patients identified by exome and genome sequencing to have a novel, pathogenic, missense variant in TUBB2A (p.Gly98Arg). They presented similarly with intellectual disability, hypotonia, and global developmental delay and varied with respect to the type of cortical brain malformation, seizure history, diagnosis of autism spectrum disorder, and other features. This case series expands the natural history of TUBB2A-related tubulinopathy while describing the presentation of a novel, pathogenic, missense variant in 3 patients.