Direct DNA sequencing is used to initially characterize the mutation, but is too laborious for routine screening. An earlier method, Restriction Fragment Length Polymorphism (RFLP) didn't need to know the sequence change beforehand, but required that the mutation affect the cleavage site of a Restriction Enzyme.
Direct DNA sequencing is employed initially to characterize mutations; however, it's too time-consuming for routine screening. In contrast, an earlier method, Restriction Fragment Length Polymorphism (RFLP), didn't necessitate prior sequence information but required the mutation to impact a Restriction Enzyme cleavage site.