Mixed-ethnic stain

Two views of a 4-dimensional graph

Manifold represents relative likelihood of various ethnic mixtures to produce
the observed DNA profile The rapist may be Hispanic (H), African-American (B), and/or European-American (C). The graph shows the likelihood of any of these races or any combination of the three producing the DNA profile collected from the victims. The "pure" (such as it is) ethnicities are represented by the corner positions of the base triangle. Every possible mixture (in the sense of mixing colors on a color wheel) is represented by a (unique point on the edge or interior of the triangle. The height of the colored manifold represents the relative likelihood of any particular ethnic blend producing the evidence that was obtained.

The case is remarkable in that a racial mixture can strongly be inferred as the contributor to the stain.

Relative chance to find the rapist's DNA among various New York ethnic mixtures.


Probable race of a stain donor (paper)
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