How the model works
The first AlphaGenome model took a million-letter DNA sequence and predicted properties across thousands of experiments from many tissues all at once. DeepMind says this parallel approach spread the model’s capacity thin and made it hard to capture subtle differences between closely related cell types.
AlphaGenome 2 is a conditional model that predicts DNA effects for one condition—defined as a tissue, cell type or state—at a time. Alongside the million-letter DNA sequence, it uses the target biological condition as input at every stage of its architecture. This allows it to learn how the same stretch of DNA is read differently across cell types.
The model can take a specific biological condition chosen from a reference catalog of cell types or generated on the fly from a scientist’s own single-cell experiment via DeepMind’s cell encoder. It also allows cross-modality imputation, enabling AlphaGenome 2 to predict missing experimental data. If a scientist inputs just one measurement, like single-cell gene activity, AlphaGenome 2 can then predict unmeasured properties, such as chromatin accessibility.
AlphaGenome 2 was trained on both bulk and single-cell data from human and mouse samples, including over 107 million individual cell profiles. It predicts the same core experimental readouts of DNA function as AlphaGenome—such as gene expression, histone modifications and chromatin accessibility—but also DNA methylation, a widely requested readout.