Disclosed is a novel method of allele profiling, or nucleic acid sieving, with pooled Sanger sequencing as a first (aka “screening”) stage; where the first step is: amplifying a single sequence, delineated by forward and reverse primers which may represent a single exon, or a segment thereof, or a contiguous stretch of multiple exons and introns. The amplicons produced from a pool of samples include the amplified sequence, and these are next converted into fragments in the standard Sanger labeling reaction. Ambiguities will appear as superposed peaks at any heterozygous position of interest, as the origin of the variant signal cannot be uniquely attributable to a specific sample, or samples, in the pool. These ambiguities may be resolved by the allele profiling process; or, resolution can be done with source-tagged primers generating source-tagged amplicons, which generate position shifts in labels, which can be decoded to resolve the ambiguities.