When a cluster of genes show linkage behaviour they : -

Linkage is the tendency of genes located close together on the same chromosome to be inherited together.
Since linked genes move together into the gametes, they do not follow Mendel's law of independent assortment; parental combinations appear more often than new combinations.
Recombination between linked genes is possible through crossing over, but its frequency is less than 50 percent; the stronger the linkage, the less recombination. Linked genes are used to make chromosome maps.
So when genes show linkage behaviour, they do not show independent assortment.