Poly-A/T trimmer


This tool removes poly-A/T tails from nucleotide sequences. The input data can be in FASTQ or in FASTA format.


Poly-A/T tails can be trimmed from either end specifying a minimum tail length. All repeats of As or Ts with at least this length will be trimmed from the read ends. A small number of tails can occur even after trimming poly-A/T tails. For example, a read that ends with AAAAATTTTT and that has been trimmed for the poly-T will still contain the poly-A.

Trimming poly-A/T tails can reduce the number of false positives during database searches, as long tails tend to align well to sequences with low complexity or sequences with poly-A tails in the database.

This tool utilizes the PRINSEQ package. The trimming is calculated with PRINSEQ options -trim_tail_left and -trim_tail_right.


The trimmed reads are saved to file called trimmed.fastq or trimmed.fasta. You can also request a log file that contains information about the filtering task and statistics about how many reads were rejected.


This tool is based on the PRINSEQ package.