A lack of ethnic diversity in people whose genomes have been sequenced is complicating precision medicine for people with non-European ancestry.

David Goldstein of Columbia University in New York City and Slavé Petrovski of the Royal Melbourne Hospital in Australia examined data from the Exome Aggregation Consortium (ExAC), which contains sequences from 60,252 people, 60.9% of whom have European ancestry. When they compared genetic variants from a cohort of 5,094 people with variants found in the ExAC and other data sets, the comparisons yielded a shorter list of potentially causative variants in people with European ancestry (6.6, on average) than in people with non-European ancestry (9.9–12.7 candidate variants, depending on ethnicity).

Precision medicine is much more precise for people with European than non-European ancestry owing to undersampling of non-European populations, the authors write.

Genome Biol. http://doi.org/bphp (2016)