Checking Read Quality - FASTQC | RC Learning Portal

FASTQC per-base sequence quality plot with generally high quality and a slight decline at read ends

FASTQC report showing per-base sequence quality, with most bases maintaining high quality across reads and slight drops at the read ends typical of Illumina data.

FASTQC per-base sequence quality plot with decreasing quality toward later read positions

FASTQC report showing per-base sequence quality, where read quality declines toward the end, indicating potential sequencing degradation or lower confidence in base calls at later positions.

FASTQC per-base sequence quality plot with pronounced quality drop-off near read ends

FASTQC report showing a decline in per-base sequence quality toward the end of reads, indicating significant quality drop-off and potential sequencing errors in later positions.