Coefficient of Relatedness and Coefficient of Inbreeding Explained

Relatedness is the probability that two individuals share an allele due to recent common ancestry. This probability is expressed as the coefficient of relatedness , denoted by the symbol r. It ranges from 0 (unrelated) to 1 (clones or identical twins).
A coefficient of inbreeding can be calculated for an individual, and is typically one-half the coefficient of relationship between the parents. (if no inbreeding)

[@sofianaftalynathan1386]

you are a life saver! amazing as usual...thank you!

[@GeneticsLessons]

Happy to help!

[@VonGontaHaus]

the coefficient of relatedness, with multiple generations brother sister matings gives a truer picture, than coefficient of inbreeding. Because coefficient of inbreeding is only 12.5% in the example shown, but in the example cited, the great-grand child is genetically like a child....and that is an alarming degree of inbreeding in breeding full brothers and sisters and then the first cousin outcome of full brother and sister matings...results in a great grandchild as if he is as child.

[@vipinkumar-yl8eh]

thank you sir for explanation ,such critical topic very simple

[@GeneticsLessons]

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[@graysenlee950]

Hi , how would you find the coefficient of relatedness between individuals S and D?

[@GeneticsLessons]

Watch my other videos in a folder "inbreeding" where I show many more examples of inbreeding calculation.

[@andreasElmann]

Following the formular you introduced in another lecture (kzbin.info/www/bejne/kHXRoZeOe9Spebs); can the coefficient of inbreeding for X (1/2)^2 x ( 1 + the coefficient of inbreeding for S) x (1 + the coefficient of inbreeding for D) = ( 0.25x1.125x1.125) = 0.31640625. What is wrong with the logic here?

[@GeneticsLessons]

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