Tools of genetic mapping

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Genetic Mapping which refers to the mapping of genes - the process of determining the map position of a gene (also called as a marker) that involves testing a linkage with a number of previously mapped markers. The various tools used are:

Mapmaker software: The analysis of the data and generation of genetic maps of large scale projects can’t be achieved without the help of a computer program, and the mapmaker software is one that helps out in such situations. Linkage is detected in a given marker, and is then converted to the recombination frequency to map the distance. The conversion is required because, the chromosomes are to be counted as having no recombination event in which two recombination events occur between the marker and the locus. And secondly because of the phenomenon of interference i.e. the probabilities of second recombination even occurring get affected by previous recombination event. Those map distances that are at adjacent intervals are additive while the frequencies are not.

Color mapping: This is another method that follows a non-mathematical procedure, of genetic mapping. The genotypes of the markers for the individual are determined in order to construct a colormap.  To deduce the colormap, genotypes were stored in the form of numerical characters that are generated during the EMBO course. After this the numerical genotypes are converted to color symbols. The numerical genotypes are as follows:

1 and 3 maternal and paternal homozygous,

2 heterozygous

4 paternal dominant genotypes

 5 maternal dominant genotypes

These numerical genotypes are converted to colors by EXCEL program that converts the white shading of the cells that has the numerical character to color as follows: Character 0, 1, 2, 3, 4, and 5, are converted to gray, yellow, green, purple, metal-blue, and light green, receptively.