Result from successive mutations of the same gene.

Multiple Alleles  result from successive mutations of the same gene.

Explanation:

Multiple alleles or polyalelia is the situation where a gene (genotype) presents three or more alleles, not just two, for the same chromosomal locus (gene address), determining a characteristic (phenotype).

Multiple alleles are the result of successive mutations in the genes of a given locus. Each mutant gene that emerges establishes a condition for the appearance of yet another new phenotypic expression of that particular character in that species.