The recombination frequency is directly proportional to the distance between genes, and the recomination values are used to locate the genes on a chromosome. Here, four genes a, b, c, and d are present with their recombination frequency of a - c = 5%, b – c = 15%, b - d = 9%, a – b = 20%, c – d = 24%, a – d = 29%.
The correct sequence of genes is a-c-b-d, and this is in accordance with the recombination frequency. 29% is the highest recombination frequency present between a and d, this signifies a and d are very far apart, and they are present at the endpoint. The distance between a and c is very less of 5%, which means they are very nearby and next to each other. Likewise, the distance between b and d is very less of 9%, which means they are very nearby and next to each other.