What is the basis of variability/polymorphism in DNA sequences?

Step-by-step solution

Allelic (again recall the definition of alleles from Chapter 4) sequence variation has traditionally been described as a DNA polymorphism if more than one variant (allele) at a locus occurs in human population with a frequency greater than 0.01. In simple terms, if an inheritable mutation is observed in a population at high frequency, it is referred to as DNA polymorphism. The probability of such variation to be observed in noncoding DNA sequences would be higher as mutations in these sequences may not have any imm