A new study analyzes data from the Mexican Biobank Project and finds regional differences in frequencies of clinically relevant genetic variants across Hispanic populations. Study identifies differences in genetic frequencies important for clinical testing. Introduces MexVar as a publicly accessible resource to support ancestry-based genetic testing. The results help to better understand genetic variability in Mexican populations. The study was published in Nature Medicine online on January 21, 2026 with DOI: 10.1038/s41591-025-04100-z. MexVar is used to improve the accuracy of genetic testing in Hispanic populations.