Final answer:
The range of PCR fragment sizes cannot be determined without additional information on the specific lengths of the alleles and primer binding sites. However, PCR can amplify variable allele lengths which, when analyzed by gel electrophoresis, would result in bands of differing sizes corresponding to each allele.
Step-by-step explanation:
To determine the range of sizes of PCR fragments that would be amplified, it's necessary to understand the specifics of the primers used for the PCR reaction. Each primer binds to a specific site on the targeted section of DNA, flanking the region that will be amplified. If there are different alleles present that result in variable lengths of DNA sequences between the priming sites, the PCR would amplify fragments of different lengths reflecting these variations. The question does not provide the exact length of the alleles or the primers, but mentions that a 597-bp PCR product was observed, implying that the template size for this allele lies within this range.
Sizes of PCR fragments vary based on the location of primer binding sites relative to each other. If the primers are designed around a polymorphic site where the alleles differ by size, the PCR could produce fragments corresponding to each allele's length. As allele sizes are not specified in the information provided, a precise range cannot be given without additional data. However, the given electrophoresis and marker data (1000 bp, 2000 bp, etc.) suggest that the PCR can resolve fragment sizes in a broad range, which could include multiple alleles of various sizes.