Q20 base and unique sequence profiles of RPCI-23 and RPCI-24 mBESs. A total of 277,490 RPCI-23 mBESs with 129 Mb and 175,647 RPCI-24 mBESs with 90 Mb were examined at each base position for Q20 base and unique sequence contents. The unique sequence fraction was in an inverse relationship with the Q20 base fraction. Two high-quality regions were identified as follows: bases 63–151 and 208–367 of RPCI-23; and bases 54–162 and 201–430 of RPCI-24 had Q20 base fractions above 90%. These regions had lower unique base contents (< 65%). RPCI-24 had a higher Q20 base content (5%–10%) and lower unique base contents (1%–2%) at some regions, especially after base 450 bp.
