Q-score distributions for all matching (blue), mismatched (red) and erroneous matching (green) overlapping read pairs in the BCV control sample. Note, the Q-score of 2 is a ‘read segment control indictor’ in the FASTQ format that tags specific final portion of the read as unreliable and unfit for downstream analyses . That Q=2 reads comprised a disproportionally large fraction of mismatched read pairs (red) is consistent with the fact that mismatched ORPs result from error during sequencing.
Chen-Harris et al. BMC Genomics 2013 14:96 doi:10.1186/1471-2164-14-96