gt;0.0884) were removed, retaining onlythird-degree or more distant relatives. Population genetic analyses, including principal component analysis (PCA), were conducted to exploredemographic patterns. Data were compared with global datasets, such as the 1000 Genomes Project (1KGP). Results: The A-C-G-T database(database.acgt.cz) contains WGS data from 1,257 healthy individuals (611 females, 646 males) after removing 10 technical outliers and 23samples with cryptic relatedness from the initial dataset (N=1,290). In the PCA, the samples cluster with other European groups from the1KGP, forming a distinct group that is well-separated from other clusters of European populations. An internal analysis revealed a possiblegenetic cline across the country. Conclusion: This Czech-specific reference improves local variant interpretation and supports precisionmedicine in Central Europe. A follow-up project (A-C-G-T 2) will expand on these data by further exploring genome variation in A-C-G-Tparticipants and analyzing patient cohorts.