Hello, I have a question about the paired end sequencing. When you have the FASTQ files of the read1 and the read2, that come from a paired sequencing, is it correct to assume that if in the position 1, of the R1 file, you have the read X in the same position of the R2 file you have the paired reads of X? Because if this is not true you need to check the name of millions of sequences and it will be very time consuming, if only one reads is missing or is in the incorrect order in R1 or R2 you will have reads paired incorrectly, could this happen? Do you know if the aligners check the names of the reads when they align paired reads or they just rely on the position of the reads? Thank you.