score:58

Accepted answer

You could accomplish this using either the cluster or tree layouts. And using a custom path generator to draw orthogonal lines connecting nodes, as in this elbow dendrogram. I guess I was feeling inspired so I gave it a shot:

score:15

I recently created some examples of using D3 to draw pedigrees in the style that most software does. There are examples for showing how to make it expand and collapse, transitions, and showing descendants as well as ancestors.

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