Mapping of The Human Genome

 The most important objective of human genome project was to construct a series of maps for each chromosome.

1. Cytogenetic map: This is a map of the chromosome in which the active genes respond to a chemical dye and display themselves as bands on the chromosome.

2. Gene linkage map: A chromosome map in which the active genes are identified by locating closely associated marker genes. The most commonly used DNA markers are restriction fragment length polymorphism (RFLP), variable number tandems repeats (VNTRS) and short tandem repeats (STRS). VNTRs are also called as minisatellites while STRs are microsatellites.

3. Restriction fragment map: This consists of the random DNA fragments that have been sequenced.

4. Physical map: This is the ultimate map of the chromosome with highest resolution base sequence. The methods for DNA sequencing are given in next blog page. Physical map depicts the location of the active genes and the number of bases between the active genes.