Understanding and perception of direct-to-consumer genetic testing in Hong Kong.

Direct-to-consumer genetic testing (DTCGT) is gaining popularity in Hong Kong (HK). As DTCGT forgoes specialist medical involvement, healthcare professionals have raised concerns regarding its validity, utility, and the public's ability to interpret DTCGT results. Thus, genetic counseling (GC) is recommended to facilitate understanding of DTCGT. This study aimed to investigate HK public's perception toward DTCGT and the importance of GC in DTCGT. A total of 304 HK adults were invited to complete a 37-item survey online. Participants' genomic literacy, understanding and attitude toward DTCGT and GC, and responses to a mock DTCGT scenario were assessed. 48% of participants were aware of DTCGT while 82% indicated an interest. 30% of participants were aware of GC services in HK; 49% were interested in GC services for understanding DTCGT results. Participants scored on average 7.6/11 in the genomic sequencing knowledge scale and were weak in limitations of genomic testing. In the mock DTCGT scenario, 73% of participants expressed concern with the positive results initially. After being explained limitations of DTCGT, 40% of participants reported decreased concern. Reduced perceived helpfulness in medical management and lifestyle modification were also reported by 35% and 27%, respectively. This HK population demonstrated a high level of awareness and interest in DTCGT. As potential DTCGT users, they might experience excess concern and overestimate the usefulness of positive DTCGT results, particularly in medical management. The importance of GC to educate and guide interpretation of DTCGT results is supported; yet the awareness and access of GC services is inadequate in HK.

A three-year follow-up study evaluating clinical utility of exome sequencing and diagnostic potential of reanalysis.

Exome sequencing (ES) has become one of the important diagnostic tools in clinical genetics with a reported diagnostic rate of 25-58%. Many studies have illustrated the diagnostic and immediate clinical impact of ES. However, up to 75% of individuals remain undiagnosed and there is scarce evidence supporting clinical utility beyond a follow-up period of >1 year. This is a 3-year follow-up analysis to our previous publication by Mak et al. (NPJ Genom. Med. 3:19, 2018), to evaluate the long-term clinical utility of ES and the diagnostic potential of exome reanalysis. The diagnostic yield of the initial study was 41% (43/104). Exome reanalysis in 46 undiagnosed individuals has achieved 12 new diagnoses. The additional yield compared with the initial analysis was at least 12% (increased from 41% to at least 53%). After a median follow-up period of 3.4 years, change in clinical management was observed in 72.2% of the individuals (26/36), leading to positive change in clinical outcome in four individuals (11%). There was a minimum healthcare cost saving of HKD$152,078 (USD$19,497; €17,282) annually for these four individuals. There were a total of six pregnancies from five families within the period. Prenatal diagnosis was performed in four pregnancies; one fetus was affected and resulted in termination. None of the parents underwent preimplantation genetic diagnosis. This 3-year follow-up study demonstrated the long-term clinical utility of ES at individual, familial and health system level, and the promising diagnostic potential of subsequent reanalysis. This highlights the benefits of implementing ES and regular reanalysis in the clinical setting.

Rapid whole-exome sequencing facilitates precision medicine in paediatric rare disease patients and reduces healthcare costs.

BACKGROUND: Rapid whole-exome sequencing (rWES) offers the potential for early diagnosis-predicated precision medicine. Previous evidence focused predominantly on infants from the intensive care unit (ICU). This study sought to examine the diagnostic and clinical utility, and the economic impact on clinical management of rWES in patients beyond infancy and ICU setting. METHODS: rWES was performed on a prospective cohort of patients with suspected monogenic disorder referred from territory-wide paediatric ICUs and non-ICUs in Hong Kong urging for rapid genetic diagnosis. All eligible families were invited. We aimed to achieve a rapid turnaround time (TAT) of 14 days. Clinical utility and costs associated with clinical management were assessed in diagnosed cases. Actual quantitative changes in healthcare utilisation were compared with a counterfactual diagnostic trajectory and/or with matched historical control whenever possible. FINDINGS: rWES were offered to 102 families and 32/102 (31%) patients received a molecular diagnosis, with a median TAT of 11 days. Clinical management changed in 28 of 32 diagnosed patients (88%), including but not limited to modifications in treatment, avoidance of surgeries, and informing decisions on redirection of care. Cost analysis was performed in eight patients. rWES was estimated to reduce hospital length of stay by 566 days and decrease healthcare costs by HKD$8,044,250 (GBP£796,460) for these eight patients. The net cost-savings after inclusion of rWES costs were estimated to be HKD$5,325,187 (GBP£527,246). INTERPRETATION: This study replicates the diagnostic capacity and rapid TAT of rWES in predominantly Chinese patients, and demonstrates diagnosis-predicated precision medicine and net healthcare savings. Findings were corroborated by evidence from multinational cohorts, combined as part of a meta-analysis. rWES merits consideration as a first-tier diagnostic tool for patients with urgent needs in the clinical setting. FUNDING: Health and Medical Research Fund, HKU Seed Fund for Basic Research, The Society for the Relief of Disabled Children, and Edward and Yolanda Wong Fund.