The Coefficient of Relatedness Calculator helps determine the genetic relationship between two individuals by quantifying the proportion of shared genes inherited from common ancestors. This tool is especially useful in fields such as biology, genetics, and evolutionary studies. It provides a precise numerical value (r), which represents the likelihood that two individuals share a specific gene due to their genetic relationship.
By inputting details such as the number of generations between each individual and their common ancestor(s), the calculator simplifies the otherwise complex process of manually calculating genetic relationships.
Formula of Coefficient Of Relatedness Calculator
The formula to calculate the coefficient of relatedness (r) is:
Where:
- n1 = number of generations from the first individual to the common ancestor.
- n2 = number of generations from the second individual to the common ancestor.
- ∑ represents the summation for all common ancestors.
To calculate the coefficient of relatedness for multiple common ancestors, compute (0.5)^(n1 + n2) for each ancestor and sum the values.
For example:
- If one common ancestor exists, calculate (0.5)^(n1 + n2).
- If multiple common ancestors exist, calculate for each and sum the results.
This method ensures accuracy in determining the genetic overlap between individuals.
Table of General Terms for Quick Reference
| Relationship Type | n1 | n2 | Coefficient of Relatedness (r) |
|---|---|---|---|
| Parent and Child | 1 | 0 | 0.5 |
| Full Siblings | 1 | 1 | 0.5 |
| Half Siblings | 1 | 1 | 0.25 |
| Grandparent and Grandchild | 2 | 0 | 0.25 |
| Aunt/Uncle and Niece/Nephew | 2 | 1 | 0.125 |
| First Cousins | 2 | 2 | 0.0625 |
| Double First Cousins | 2 | 2 | 0.125 |
This table offers quick reference values, eliminating the need for manual calculations for common relationships.
Example of Coefficient Of Relatedness Calculator
Let’s calculate the coefficient of relatedness between an individual and their uncle:
- From the individual to the common ancestor (grandparent), n1 = 2.
- From the uncle to the same common ancestor, n2 = 1.
Using the formula:
r = (0.5)^(2 + 1)
r = (0.5)^3 = 0.125
Thus, the coefficient of relatedness between the individual and their uncle is 0.125.
For multiple common ancestors, repeat the calculation for each and sum the results.
Most Common FAQs
The coefficient of relatedness is use to measure genetic overlap between individuals. It’s commonly applied in genetics, biology, and studies involving heredity or evolutionary relationships.
It simplifies the process of determining genetic relationships by automating complex calculations. This allows researchers to focus on analysis without spending time on manual computations.
Yes, the formula applies to any species with a clear lineage. It’s often use in animal breeding, conservation, and evolutionary biology studies.