Evolving Molecular Marker Technologies in Plants: From RFLPs to GBS

Analysis of DNA-sequence variation (or allelic state) at a specific chromosomal location in an individual/genotype is referred to as genotyping. Variation in the DNA sequence may or may not have functional significance. For example, variation may result either in a synonymous or non-synonymous change in a codon. Such alterations may either cause a favorable change or deleterious mutations (mis-sense or non-sense) in an organism. Genetic variation may be small changes in frame (point-mutations, substitutions) or frame-shifts (insertions or deletions) (Jones et al. 2009). Nevertheless, these variations have been used as molecular markers to understand genome architecture as well as for plant breeding applications. Marker genotyping has various applications including parental genotype selection,