UW ISeqU: Clinical Impact of Whole-genome Sequencing in Adults

This is a prospective observational cohort study evaluating the use of clinical whole genome sequencing in adults with unexplained medical conditions, atypical disease courses, or clinical presentations for which a genetic contribution is suspected. Participants will be identified at the University of Washington Medicine sites (UW Montlake and Harborview Medical Center). The study is intended to characterize how genome sequencing can be incorporated into adult clinical care. Participation is voluntary and does not replace standard diagnostic evaluation or treatment.

Potential participants will be identified through review of hospital admissions and referrals from treating clinicians or specialty services. Informed consent may be completed in person, by telephone, or by secure videoconference. When a hospitalized participant is unable to provide consent because of illness or impaired decision-making capacity, consent may be obtained from a legally authorized representative in accordance with applicable requirements. During consent, participants will indicate whether they wish to receive ACMG medically actionable secondary findings and whether they agree to future contact.

After enrollment, the study team will collect clinical and phenotypic information relevant to genomic interpretation. Information may include the participant's presenting symptoms, medical and family history, prior diagnostic testing, medications, hospital course, and subsequent clinical care. Data will be obtained from participant or family interview, review of the electronic health record, and communication with the treating team. Clinical information from before and after sequencing will be collected to support interpretation and to evaluate the downstream effects of genomic findings.

The only physical procedure is collection of a biospecimen for genomic testing. Research blood collection will be coordinated with a clinically indicated blood draw to avoid an additional venipuncture. Alternatively, a buccal swab may be used.

A close biological relative may also be enrolled as a genetic comparator when this would assist in genetic interpretation. Comparator participation is optional. Comparators will provide a buccal specimen and limited identifying information needed for laboratory testing. Their medical records will not be reviewed.

Whole-genome sequencing will be performed and interpreted by GeneDx, a CLIA-certified laboratory. Variants will be classified using current ACMG/AMP standards. Findings will be assessed in relation to the participant's phenotype and may be categorized as diagnostic, contributory, secondary, or non-contributory. Variants of uncertain significance may be reported when considered relevant by the clinical laboratory.

Participants may choose whether to receive medically actionable secondary findings in genes recommended by the ACMG. Comparator analysis will generally be limited to variants relevant to interpretation of the enrolled participant. A comparator may receive a result when a clinically significant variant identified in the participant is also present in the comparator or when the comparator has separately chosen to receive an eligible secondary finding.

Clinically relevant results will be returned by a genetic counselor or clinical geneticist by telephone, secure video visit, or in person. Results will be communicated to the clinical team and will be made available in the medical record. When appropriate, participants may be advised to discuss additional evaluation, surveillance, treatment, or family testing with their clinicians or to seek consultation with a medical genetics referral. Clinical care resulting from a genomic finding, including laboratory testing, imaging, specialist referral, or treatment, is not provided as a study procedure.

In addition to the clinical laboratory analysis, genomic and clinical data may be used for exploratory research. These analyses may include pharmacogenomic assessment, evaluation of gene-disease relationships, or other studies of disease mechanisms and treatment response. Exploratory research findings will not be returned clinically.

The study team will review participants' medical records for up to 3 years after enrollment to evaluate the downstream clinical effects of sequencing, including changes in diagnosis, treatment, surveillance, referrals, and family counseling. Participants may also be invited to complete a brief survey or interview about their experience with genetic testing and result disclosure. Participants who agree to future contact may be contacted if clinically important new information or a meaningful reinterpretation of their genomic findings becomes available.

Clinical and genomic data will be stored using coded study identifiers on secure systems. The linkage between study identifiers and participant identities will be maintained separately, with access restricted to authorized study personnel. Genomic data may be retained for future reanalysis as scientific knowledge changes. Individual genetic variants may be submitted in de-identified form to public variant databases such as ClinVar; raw genomic data and medical records will not be included in those submissions.