A Patient Is Being Tested to Determine Whether He Has

Multiple Choice

A patient is being tested to determine whether he has the factor V Leiden mutation by PCR-RFLP analysis. PCR is performed on the patient's DNA and cut with HindIII. The mutation-positive control sample had a single band of expected size, and the mutation-negative control sample had a slightly larger band. The patient's specimen had two bands, one that was the same size as the mutation-positive control band and the other the same as the mutation-negative control. Which of the following is the correct interpretation of these results?

A) The patient does not have the factor V Leiden mutation.
B) The patient is heterozygous for the factor V Leiden mutation.
C) The patient is homozygous for the factor V Leiden mutation.
D) The results are not valid, and the assay should be repeated.