Engelsk oversættelse

Direct sequencing[edit]

The first reported method of methylation analysis using bisulphite-treated DNA utilized PCR and standard dideoxynucleotide DNA sequencing to directly determine the nucleotides resistant to bisulphite conversion.[6] Primers are designed to be strand-specific as well as bisulphite-specific (i.e., primers containing non-CpG cytosines such that they are not complementary to non-bisulphite-treated DNA), flanking (but not involving) the methylation site of interest. Therefore, it will amplify both methylated and unmethylated sequences, in contrast to methylation-specific PCR. All sites of unmethylated cytosines are displayed as thymines in the resulting amplified sequence of the sense strand, and as adenines in the amplified antisense strand. This technique required cloning of the PCR product prior to sequencing for adequate sensitivity, and therefore was a very labour-intensive method unsuitable for higher throughput. Alternatively, nested PCR methods can be used to enhance the product for sequencing.

All subsequent DNA methylation analysis techniques using bisulphite-treated DNA is based on this report by Frommer et al. (Figure 2) ([7]). Although most other modalities are not true sequencing-based techniques, the term "bisulphite sequencing" is often used to describe bisulphite-conversion DNA methylation analysis techniques in general.

hej nogen der kan hjælpe mig med at oversætte den her tekst...den er meget vigtig og har brug for hjælp med at oversætte da jeg ikke lige er den bedste til engelsk:/