Often the male component comprises a tiny fraction of the DNA recovered from fingernails with most of the DNA originating from the victim herself. Also, unlike mixtures of sperm and non-sperm cells, it is not possible to perform a differential extraction procedure to subfractionate and purify the DNA further into its constituent male and female components. The inability to obtain a standard (autosomal) STR profile from the male, despite the presence of male cells, is the result. However, Y chromosome analysis may yield the genetic profile of the perpetrator due to the ability of the system to ignore the overwhelming quantities of female DNA present.

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