Reported environmental exposures are inversely associated with obtaining a genetic diagnosis in the Undiagnosed Diseases Network

The Undiagnosed Diseases Network: Characteristics of solvable applicants and diagnostic suggestions for nonaccepted ones

PURPOSE

Can certain characteristics identify as solvable some undiagnosed patients who seek extensive evaluation and thorough record review, such as by the Undiagnosed Diseases Network (UDN)?

METHODS

The UDN is a national research resource to solve medical mysteries through team science. Applicants provide informed consent to access to their medical records. After review, expert panels assess if applicants meet inclusion and exclusion criteria to select participants. When not accepting applicants, UDN experts may offer suggestions for diagnostic efforts. Using minimal information from initial applications, we compare features in applicants who are not accepted with those who are accepted and either solved or still not solved by the UDN. The diagnostic suggestions offered to nonaccepted applicants and their clinicians were tallied.

RESULTS

Nonaccepted applicants were more often female, older at first symptoms and application, and longer in review compared with accepted applicants. The accepted and successfully diagnosed applicants were younger, shorter in review time, more often non-White, of Hispanic ethnicity, and presenting with nervous system features. Half of nonaccepted applicants were given suggestions for further local diagnostic evaluation. A few seemed to have 2 major diagnoses or a provocative environmental exposure history.

CONCLUSION

Comprehensive UDN record review generates possibly helpful advice.

Clinical Trials for Special Populations: Children, Older Adults, and Rare Diseases

Research cannot maximize population health unless it improves health for all members of the public, including special populations such as children, older adults, and people living with rare diseases. Each of these categories require special considerations when planning and performing clinical trials, and common threads of ethical conduct of research in vulnerable populations appear throughout. In this review, definitions of each of the three categories of special population (children, older adults, and rare diseases) are discussed in terms of US research regulations, the unique challenges to conducting clinical trials for these special populations, critical ethical issues, and opportunities for innovative ways to design and operationalize clinical trials in special populations. Additional critical attention is focused on factors that influence the generalizability of study results to reduce health disparities, as well as the importance of community engagement and advocacy groups that can help to educate potential trial participants of the benefits of clinical trial participation.

New Diagnostic Approaches for Undiagnosed Rare Genetic Diseases

Accurate diagnosis is the cornerstone of medicine; it is essential for informed care and promoting patient and family well-being. However, families with a rare genetic disease (RGD) often spend more than five years on a diagnostic odyssey of specialist visits and invasive testing that is lengthy, costly, and often futile, as 50% of patients do not receive a molecular diagnosis. The current diagnostic paradigm is not well designed for RGDs, especially for patients who remain undiagnosed after the initial set of investigations, and thus requires an expansion of approaches in the clinic. Leveraging opportunities to participate in research programs that utilize new technologies to understand RGDs is an important path forward for patients seeking a diagnosis. Given recent advancements in such technologies and international initiatives, the prospect of identifying a molecular diagnosis for all patients with RGDs has never been so attainable, but achieving this goal will require global cooperation at an unprecedented scale.

The joy and duty of a marginal teratologist

On the occasion of this anniversary of the Society for Birth Defects Research and Prevention, I accept the invitation to offer personal reflections on the earlier days of the Society and the importance of the discipline. My focus is on what few contributions I have offered, but more, on the value of having the teratologist's perspective on other aspects of my career in medical genetics and genetic epidemiology. Treating my professional life as a development biologist (of which teratologists are a breed), I recount the institutions I have been at, but more importantly, the people I have been influenced by, more often than not accomplished teratologists. The one big thought I wish to leave is the primacy and criticality of being mentored and mentoring at ALL stages of a career.

Identifying disease-causing mutations in genomes of single patients by computational approaches

Over the last decade next generation sequencing (NGS) has been extensively used to identify new pathogenic mutations and genes causing rare genetic diseases. The efficient analyses of NGS data is not trivial and requires a technically and biologically rigorous pipeline that addresses data quality control, accurate variant filtration to minimize false positives and false negatives, and prioritization of the remaining genes based on disease genomics and physiological knowledge. This review provides a pipeline including all these steps, describes popular software for each step of the analysis, and proposes a general framework for the identification of causal mutations and genes in individual patients of rare genetic diseases.