Patent ID: 7371531

Claim:
A method of detecting, verifying, and/or calibrating the extraction of nucleic acid from a biological sample, the method comprising: a) obtaining a biological sample; b) combining one or more reference nucleic acids with the biological sample; c) extracting nucleic acid from the biological sample concurrently with and/or after step b to yield an extract; and d) detecting the presence of and/or quantifying the amount of reference nucleic acid in the extract; e) estimating the amount of non-reference nucleic acid present in the composition before the extraction step by i) quantifying the amount of total nucleic acid and the amount of reference nucleic acid in the extract of step c; ii) comparing the amount of reference nucleic acid in the extract of step c to the amount of reference nucleic acid combined with the biological sample in step a to calculate a ratio of extraction efficiency; and iii) subtracting the amount of reference nucleic acid in said extract from the amount of total nucleic in said extract to yield the amount of non-reference nucleic acid in said extract; and iv) dividing the amount of non-reference nucleic acid in the extract by the ratio of extraction efficiency, wherein the reference nucleic acid is capable of being detected and/or quantified without an amplification step, and further wherein the reference nucleic acid is capable of being detected without interference from material in the biological sample.