Mixtures

Mixtures of DNA types from more than one source of semen are more difficult to interpret. The greater the number of the victim's sex partners, either by consent or rape, the greater the likelihood that the inmate's type will be masked by the presence of other types and not afford a clear elimination.

If an assault or homicide case involves possible blood transfers from multiple assailants and/or victims, the same issues of mixtures and masking may apply.

In sex cases with mixtures, or where an exclusion of the defendant is contrary to otherwise strong evidence, consider the possibility that the victim may have had an unrevealed prior consensual sexual partner within 24 to 48 hours prior to the rape.

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