Making Rare Diseases Count 2026

For many rare diseases, early diagnosis is critical to enabling timely treatment, informed care decisions and better outcomes. It also serves a broader purpose: by identifying cases early and systematically, it generates more accurate prevalence estimates that strengthen the overall evidence base for rare diseases. The economic case for improving early diagnosis is compelling, even before factoring in the value of the data these tools produce. A 2022 study found that delays in diagnosis across seven rare conditions led to avoidable costs of up to $517,000 per patient.29 While these figures reflect a limited set of diseases, they illustrate how prolonged diagnostic journeys can impose substantial economic and human costs that are echoed across many rare conditions. One way to streamline early diagnosis is to expand newborn screening (NBS). In many countries, newborns are screened through state-sponsored, population-level NBS programmes. The scope and quality of these programmes vary dramatically. Some screen for more than 60 conditions, others cover only a few and some countries have yet to establish national NBS programmes. At the leading edge, researchers are exploring the use of next-generation sequencing (NGS) for newborn screening. Numerous initiatives worldwide are now evaluating which conditions to include, how results should be returned and what ethical and operational safeguards are required. In parallel, commercial offerings are beginning to emerge from companies such as Nurture Genomics, bringing NGS-based newborn screening into clinical settings while public health frameworks continue to evolve. Since NBS is not diagnostic, programmes are expanding follow-up testing, both to confirm findings and to detect cases screening may miss. Whole genome sequencing (WGS), pioneered in critically ill children, is now applied more broadly, including to adults who have lived for years without a diagnosis. Advances in next-generation diagnostics and AI are also creating new tools to uncover elusive conditions and address inequities in diagnosis. The Genetic Alliance’s iHope programme illustrates this potential. As the largest free clinical genomic testing effort worldwide, iHope has enabled clinical WGS and whole exome sequencing (WES) for more than 3,000 families from 30 clinical sites in 14 LMICs and 5 HICs. In a recent analysis of 1,004 participants, 41.4% received a molecular diagnosis and over two-thirds of those diagnoses were associated with changes in clinical management, genetic counselling or avoidance of further testing.30 The programme also empowers families by granting them control of their genomic data through a user-centric platform. Collaborative initiatives such as the Undiagnosed Hackathons, founded and led by the Swedish non-profit the Wilhelm Foundation, show how cross-disciplinary teams are working together to tackle cases that remain unsolved even with today’s most advanced technologies.31 These efforts also generate data and insights into the estimated 350 million people worldwide living with undiagnosed conditions.32 Clinician awareness is also critical to improving early detection. Accredited continuing education programmes have shown tangible results: paediatric neurologists who participated in rare disease training on Medscape – the world’s largest medical education platform – ordered 69% more genetic tests than those who did not.33 Such findings highlight the importance of investing in professional education as a practical lever for earlier diagnosis.2.3 Improve newborn screening and diagnostic capacity Making Rare Diseases Count: How Better Data Can Unlock a Multitrillion-Dollar Opportunity 17