As the project started sequencing in 2008 it holds a wide range of read lengths, the Illumina and SOLiD data range between 25bp to 160bp read lengths. Our sequence index file report read and base counts for each fastq file which can be used to find this out more precisely. For the final analysis phase of the project only Illumina data which is 70bp or longer was used and where required samples were sequenced again to match this criterion.