This visualization presents a hierarchical tree layout of gene expression data, where nodes cluster into branching paths and leaf labels reveal array probe identifiers. Built with D3 v5, it loads JSON data and renders the hierarchy using the `tree` layout, drawing curved links via `linkHorizontal` and node labels as SVG text elements. The visualization supports pan and zoom through D3’s `zoom` behavior, while CSS styling with the Playfair Display font and light text shadows enhances readability over the teal connection strokes.