Читать книгу Genotyping by Sequencing for Crop Improvement - Группа авторов - Страница 50

The simplest method of genotyping is whole‐genome resequencing of genotypes followed by the reference‐based assembly for variant calling. But as the majority of the genome is noncoding, these noncoding regions are also reflected in the variant file generated by the mapping of the reads which in turn increases the complexity of analysis as well as interpretation. Reduced representation approaches like RAD‐seq and GBS methods have solved this issue as in spite of sequencing the whole genome, these methods are confined to coding/genic regions only. For this, we first digest the DNA with methylation‐sensitive restriction enzyme with the hypothesis that DNA is more methylated in the noncoding region hence the digestion will be limited to coding regions only. The restricted ends generated are then ligated with adapters and sequenced. Other widely used sequencing‐based technologies are exome sequencing (Exom‐seq) and double digest RAD‐seq (ddRAD‐seq).