Meiotic Mapping
- Determines the relative order and distances between genes on a chromosome.
- Uses segregation patterns of genetic markers observed during meiosis to construct a genetic map.
- Helps locate genes underlying traits or genetic disorders, informing diagnosis and treatment.
Definition
Section titled “Definition”Meiotic mapping is a method used to study the order and location of genes on a chromosome by observing the segregation patterns of genetic markers during meiosis, the cell-division process that produces gametes. This method permits determination of distances between genes and construction of a genetic map showing their relative positions.
Explanation
Section titled “Explanation”Meiotic mapping relies on tracking how genetic markers are inherited as organisms undergo meiosis. By observing which markers are co-inherited and which segregate independently, researchers infer the relative positions of genes: markers that are frequently inherited together are inferred to be close on the chromosome, while markers that assort separately are inferred to be farther apart. The resulting genetic map is a diagram that represents these relative positions.
Examples
Section titled “Examples”Eye color mapping
Section titled “Eye color mapping”Using genetic markers to study inheritance of a trait such as eye color: crossbreeding individuals with different eye colors and observing segregation patterns of markers associated with eye color allows researchers to locate the gene responsible on a chromosome. For example, if a segregation pattern shows the gene for blue eyes is always inherited along with a marker for brown eyes, researchers can conclude the gene for blue eyes is located close to the marker for brown eyes on the chromosome.
Mapping genes for genetic disorders
Section titled “Mapping genes for genetic disorders”Studying disorders such as cystic fibrosis or sickle cell anemia: researchers use genetic markers to determine the chromosome location of the gene responsible for the disorder. By observing segregation patterns of the markers, they can determine whether the disorder is caused by a mutation in a single gene or by interaction of multiple genes.
Use cases
Section titled “Use cases”- Locating genes responsible for specific traits.
- Identifying the chromosomal positions of genes involved in genetic disorders, supporting diagnosis and development of treatments.
Related terms
Section titled “Related terms”- Meiosis
- Genetic marker
- Genetic map
- Chromosome
- Gamete
- Trait
- Mutation