2. Human Genome Project
1- Identifying new genes
2- Identifying its function
Gene Mapping
Main Goals
Through
Developing Tools
3. Gene mapping: It is a tool used to
1. locate the genes on the chromosome
2. Calculate the distance between genes on the same
chromosome
• can offer firm evidence that a disease transmitted
from parent to child is linked to one or more genes.
• provides clues about which chromosome contains
the gene and precisely where the gene lies on that
chromosome.
4. How do researchers create a genetic map?
• researchers collect blood or tissue samples from members of
families in which a certain disease or trait is prevalent.
• the scientists isolate DNA from these samples and examine
it for unique patterns that are seen only in family members
who have the disease or trait. These characteristic patterns
in the chemical bases that make up DNA are referred to as
markers.
• The closer two markers are on the chromosome, The more
likely they are to passed on to the nest generation together.
That’s why gene mapping depends on Recombination
5. Aa Bb
Black eyes
Black hair
Aa bb
Brown eyes
Brown hair
AB ab Ab aB
ab AaBb aabb Aabb aaBb
Black eyes
Black hair
Brown eyes
Brown hair
Black eyes
Brown hair
Brown eyes
Black hair
Paternal Recombinant
7. Uses of gene mapping :
- Identify genes responsible for disease:
Heritable disease
Cancer
-Identify genes responsible for traits:
Plant or animal
Disease resistance
Meat or milk production
