Rare Diseases and the New Era of Diagnosis and Treatment
Sri Aditya Domakuntla, Umesh Ummalaneni, and Saharsh Chalumalla
03/09/2026
Rare diseases are individually uncommon but collectively affect hundreds of millions of people. This narrative review examines how rare diseases are defined, why diagnosis is frequently delayed, how orphan-drug policy has changed treatment development, and how genomic sequencing, artificial intelligence, gene therapy, and gene editing are reshaping care. The literature was identified through targeted searches of biomedical databases and authoritative government, clinical, and patient-advocacy sources, with emphasis on publications from 2015 through June 2026. Evidence indicates that patients often experience years of diagnostic delay and that only a small share of known rare diseases has an approved treatment. Recent advances, including personalized in vivo gene editing, demonstrate the possibility of therapies designed for extremely small patient populations. However, most personalized and gene-editing approaches remain experimental, require specialized infrastructure, and have limited long-term safety and effectiveness data. Progress is also distributed unevenly: access to newborn screening, genomic testing, specialists, and orphan drugs is substantially greater in well-resourced health systems. Scientific innovation therefore must be paired with stronger referral networks, diverse genomic data, sustainable financing, international collaboration, and patient-centered policy.