Precision medicine: Rare diseases and community genetics

Precision medicine is based on the premise that genomic analysis radically changes the nature and scope of therapeutic medicine. While genome sequencing has revolutionized the study of human disease, to date progress in translating genomic knowledge into treatments for inherited disorders has been less apparent. However, increasing attention on the relationship(s) between rare diseases (RDs) and precision medicine should significantly accelerate this process, as evidenced by the increasing numbers of molecular therapies receiving approval from the U.S. Food and Drug Administration. There are an estimated 7000 RDs, a majority of which affect <1/million people; but, collectively, it has been calculated that in high-income countries ≥1/17 persons have a RD. RDs represent both a significant health challenge and a major economic burden for many affected individuals and their families, and although many are life-threatening, they often remain undiagnosed or misdiagnosed. Unfortunately, global progress in resolving these issues has been hindered by basic problems such as differing national and regional definitions, from a RD prevalence of 1 to 5/10,000 affected persons in Europe and Australia to 1/500,000 in China. There also has been failure to recognize that many RDs originated as founder mutations and are community-specific, an especially important consideration in populations where community endogamy is the rule and close-kin marriage is traditional. The near-global transition from a communicable to a predominantly noncommunicable disease profile has, however, served to highlight the importance of genetics in medicine, and resulted in a rapidly growing focus on RDs. Against this background, collaborative international programs to facilitate the prevention and curative treatment of RDs merit urgent adoption and support.