Missequencing

Missequencing refers to errors that occur during the process of DNA sequencing. These errors can manifest in several ways, most commonly as incorrect base calls, where a nucleotide base (adenine, guanine, cytosine, or thymine) is misidentified. Other types of missequencing include insertion or deletion errors, where extra bases are added or bases are missing from the sequence, leading to frameshift mutations in downstream analyses.

The causes of missequencing are varied and can arise at multiple stages of the sequencing workflow. These include errors in sample preparation, such as DNA damage or contamination, issues with the sequencing chemistry itself, instrument malfunctions, or limitations in the computational algorithms used to assemble and interpret the raw sequencing data. Different sequencing technologies, like Sanger sequencing or next-generation sequencing (NGS) platforms, have distinct error profiles and frequencies. For instance, older technologies might have higher substitution error rates, while certain NGS platforms can be prone to indel errors.

The impact of missequencing depends heavily on the application. In research, missequencing can lead to incorrect conclusions about gene function, genetic variation, or evolutionary relationships. In clinical settings, missequencing can result in misdiagnosis, incorrect treatment decisions, or a false sense of security regarding the presence or absence of disease-causing mutations. Therefore, rigorous quality control measures, including data validation and cross-referencing with other datasets or experimental results, are crucial to minimize the impact of missequencing and ensure the reliability of sequencing data.