read length for ChIA-PET data provided by Yijun Ruan et al.

Question

[caochch]

I downloaded the ChIA-PET data from https://www.ncbi.nlm.nih.gov/sra/SRX1210752 which was provided by "CTCF-Mediated Human 3D Genome Architecture Reveals Chromatin Topology for Transcription. Tang et al. Cell, 2015, 163(7): 1611-1627.".

The authors claimed that DNA products were then subjected to size-selection and paired-end sequencing (2×150 bp) using Illumina Hi-Seq 2500.

However, the reads length in the downloaded fastq ranged from 70 to 302bp. This confused me a lot.

I would appreciate any help or suggestions.

Thanks Cao