Improving access to exome sequencing in a medically underserved population through the Texome Project.

PURPOSE: Genomic medicine can end diagnostic odysseys for patients with complex phenotypes; however, limitations in insurance coverage and other systemic barriers preclude individuals from accessing comprehensive genetics evaluation and testing. METHODS: The Texome Project is a 4-year study that reduces barriers to genomic testing for individuals from underserved and underrepresented populations. Participants with undiagnosed, rare diseases who have financial barriers to obtaining exome sequencing (ES) clinically are enrolled in the Texome Project. RESULTS: We highlight the Texome Project process and describe the outcomes of the first 60 ES results for study participants. Participants received a genetic evaluation, ES, and return of results at no cost. We summarize the psychosocial or medical implications of these genetic diagnoses. Thus far, ES provided molecular diagnoses for 18 out of 60 (30%) of Texome participants. Plus, in 11 out of 60 (18%) participants, a partial or probable diagnosis was identified. Overall, 5 participants had a change in medical management. CONCLUSION: To date, the Texome Project has recruited a racially, ethnically, and socioeconomically diverse cohort. The diagnostic rate and medical impact in this cohort support the need for expanded access to genetic testing and services. The Texome Project will continue reducing barriers to genomic care throughout the future study years.

Novel hemizygous single-nucleotide duplication in RPGR in a patient with retinal dystrophy and sensorineural hearing loss.

BACKGROUND: The RPGR gene has been associated with X-linked cone-rod dystrophy. This report describes a variant in RPGR detected with exome sequencing (ES). Genes like RPGR have not always been included in panel-based testing and thus genome-wide tests such as ES may be required for accurate diagnosis. METHODS: The Texome Project is studying the impact of ES in medically underserved patients who are in need of genomic testing to guide diagnosis and medical management. The hypothesis is that ES could uncover diagnoses not made by standard medical care. RESULTS: A 58-year-old male presented with retinitis pigmentosa, sensorineural hearing loss, and a family history of retinal diseases. A previous targeted gene panel for retinal disorders had not identified a molecular cause. ES through the Texome Project identified a novel, hemizygous variant in RPGR (NM_000328.3: c.1302dup, p.L435Sfs*18) that explained the ocular phenotype. CONCLUSIONS: Continued genetics evaluation can help to end diagnostic odysseys of patients. Careful consideration of genes represented when utilizing gene panels is crucial to ensure an accurate diagnosis. Medically underserved populations are less likely to receive comprehensive genetic testing in their diagnostic workup. Our report is an example of the medical impact of genomic medicine implementation.

Clinical genome sequencing: Three years' experience at a tertiary children's hospital.

PURPOSE: Genome sequencing (GS) may shorten the diagnostic odyssey for patients, but clinical experience with this assay in nonresearch settings remains limited. Texas Children's Hospital began offering GS as a clinical test to admitted patients in 2020, providing an opportunity to study GS utilization, possibilities for test optimization, and testing outcomes. METHODS: We retrospectively reviewed GS orders for admitted patients for a nearly 3-year period from March 2020 through December 2022. We gathered anonymized clinical data from the electronic health record to answer the study questions. RESULTS: The diagnostic yield over 97 admitted patients was 35%. The majority of GS clinical indications were neurologic or metabolic (61%) and most patients were in intensive care (58%). Tests were often characterized as candidates for intervention/improvement (56%), frequently because of redundancy with prior testing. Patients receiving GS without prior exome sequencing (ES) had higher diagnostic rates (45%) than the cohort as a whole. In 2 cases, GS revealed a molecular diagnosis that is unlikely to be detected by ES. CONCLUSION: The performance of GS in clinical settings likely justifies its use as a first-line diagnostic test, but the incremental benefit for patients with prior ES may be limited.

Association between anxiety symptoms and Alzheimer's disease biomarkers in cognitively healthy adults: A systematic review and meta-analysis.

OBJECTIVE: Anxiety has been identified as both a risk factor and prodromal symptom for Alzheimer's disease (AD) and related dementias, however, the underlying neurobiological correlates remain unknown. The aim of this systematic review and meta-analysis was to examine the association between anxiety symptoms and two defining markers of AD neuropathology: amyloid-beta (Aß) and tau. METHODS: Systematic literature searches were conducted across 5 databases. Studies investigating the relationship between anxiety and AD neuropathology (i.e., Aß and/or tau) in cognitively healthy adults were eligible. Where possible, effect sizes were combined across studies, for Aß and tau separately, using random-effects meta-analyses. Sensitivity analyses were performed to assess whether results differed according to anxiety type (i.e., state and trait) and biomarker assessment modality (i.e., positron emission tomography and cerebrospinal fluid). RESULTS: Twenty-seven studies reporting data from 14 unique cohorts met eligibility criteria. Random-effects meta-analyses revealed no associations between self-reported anxiety symptoms and either Aß (13 studies, Fisher's z = 0.02, 95% confidence interval [CI] -0.01-0.05, p = 0.194) or tau (4 studies, Fisher's z = 0.04, 95% CI -0.02-0.09, p = 0.235). Results remained unchanged across sensitivity analyses. CONCLUSIONS: In cognitively healthy adults, meta-analytic syntheses revealed no associations between anxiety symptoms and either Aß or tau. There is a critical need, however, for larger studies with follow-up periods to examine the effect of anxiety symptom onset, severity, and chronicity on AD neuropathology. Additionally, further research investigating other potential neurobiological correlates is crucial to advance scientific understanding of the relationship between anxiety and dementia.

Prenatal genetic counseling practices regarding recommendations for cancer genetic counseling: A retrospective chart review from two academic institutions.

Prenatal and preconception genetic counselors are trained to take patient pedigrees to evaluate for potential risks for genetic conditions, including hereditary cancer syndromes. However, little research has been published on how often prenatal/preconception genetic counselors provide recommendations for cancer genetic counseling solely based on a family history of cancer. Therefore, this study sought to (a) characterize the types of cancers recognized for a cancer genetic counseling recommendation, (b) analyze appointment indications associated with discussion documentation, and (c) investigate how often National Comprehensive Cancer Center (NCCN) genetic testing criteria for Hereditary Breast and Ovarian Cancer syndrome (HBOC) and Lynch syndrome were met and how often a recommendation for cancer genetic counseling was made. A retrospective chart review and pedigree analysis were performed for prenatal/preconception genetic counseling patients with a family history of cancer seen at two academic institutions between August 10, 2019, and December 1, 2019. In the 170 charts included, a recommendation for cancer genetic counseling was documented in 40% of all genetic counseling summaries and in 59.2% of summaries when NCCN genetic testing criteria for HBOC and/or Lynch syndrome was met. Using chi-squared and logistic regression analysis, these data support that individuals were significantly more likely to receive a recommendation when NCCN genetic testing criteria were met (OR = 5.01, p < .001) or when the family history contained two or more types of cancer (OR = 2.24, p = .02). Overall, this study identified the NCCN genetic testing criteria for HBOC and Lynch syndrome for which recommendations for cancer genetic counseling were commonly missed. This characterization suggests that continuing education for prenatal and preconception genetic counselors on updated NCCN guidelines may be helpful for improving rates of cancer genetic counseling referrals, uptake of genetic testing, and cancer screening recommendations.