Physical maps

Definition

Physical maps represent the physical distances between landmarks on a DNA strand, often measured in base pairs. They are essential for understanding the structure and organization of genomes.

5 Must Know Facts For Your Next Test

1. Physical maps help identify the locations of genes and genetic markers on chromosomes.
2. They are different from genetic maps, which are based on recombination frequencies rather than physical distance.
3. Physical mapping techniques include restriction mapping, fluorescence in situ hybridization (FISH), and sequence-tagged sites (STS).
4. These maps provide a foundation for sequencing entire genomes by offering a framework for assembling sequence data.
5. Physical maps are crucial for identifying structural variations in the genome that may be associated with diseases.

Review Questions

• What is the primary difference between physical maps and genetic maps?
• Name two techniques used to create physical maps of genomes.
• Why are physical maps important for genome sequencing projects?

Related terms

Genetic Map: A map that shows the relative positions of genes based on recombination frequencies.

Restriction Mapping: A technique used to determine the location of restriction enzyme sites on a segment of DNA.

Fluorescence In Situ Hybridization (FISH): A technique used to identify specific DNA sequences on chromosomes using fluorescent probes.