Read length

Read length value is the length of called reads measured in base pairs. The Read Length histogram presents all filtered and trimmed library reads reported in the output BAM file and the mean read length in base pairs. The shape of the histogram should closely resemble the library size distribution trace, without the adapter sequences.

  1. The y-axis provides the read count.

  2. The x-axis provides the read length in base pairs.

In addition to the loading density and read filtering and trimming, the average library read length also affects the total sequencing run throughput. Read length is considered in the total sequencing run throughput. For example, a sequencing run on an Ion 530™ chip produces about 15 million final library reads:

  • If the average read length is 300 bp, then the approximate throughput is 15,000,000 reads * 300 bp = 4.5 Gbp.

  • If the average read length is 400 bp, then the approximate throughput is 15,000,000 * 400 bp = 6 Gbp.

For more information, see How to assess an Ion S5™/Ion GeneStudio™ S5 sequencing run report User Bulletin (Pub. No. MAN0017983).

Related Topics
Parent topic: Run report metrics