Practice question

Genetic linkage describes co-segregation of loci located on same chromosome during meiosis because parental allele combinations remain on same chromatid unless crossover separates them. Independent assortment traditionally applies to genes on different chromosomes where homologue segregation randomises combinations, or distant syntenic loci where recombination approaches fifty percent effectively randomising. Linked genes form linkage group showing excess parental gametes in test crosses. Thomas Hunt Morgan first documented linkage in Drosophila with body colour and wing size establishing chromosome theory and basis for future mapping.