Mapping-by-sequencing is a technique in basic genetic research that combines classical genetic mapping concepts with the power of next-generation-sequencing to enable the mapping and molecular identification of phenotype-causing mutations from a single experiment.
After having obtained, e.g., from a forward genetic screen, a mutant strain of an organism with a particular phenotype, the classical approach towards identification of the underlying causative mutation would be to
- perform mapping crosses to probe for linkage between the unknown mutation and selected markers with known location on the genome in order to determine the approximate genomic region that the mutation resides in, then
- sequence candidate DNA stretches in this region to identify the precise nature of the mutation.
Modern mapping-by-sequencing approaches, in contrast, use just one set of genome-wide sequencing data obtained from mapping-cross progeny and suitable parent strains to simultaneously:
- discover available marker mutations for linkage analysis,
- map the causative mutation using these markers, and
- identify candidate mutations
Since genome-wide sequencing will often reveal a few hundreds to many thousands of marker variants that should be considered together in the linkage analysis, mapping-by-sequencing data is typically analyzed with dedicated computational tools.
This community aims at being a hub for discovering primary literature, datasets and tools relevant for mapping-by-sequencing.
Software