Which statement best describes the advantage of MPS over traditional STR methods?

Which statement best describes the advantage of MPS over traditional STR methods?

• A. It runs faster but provides less information.
• B. It sequences a single locus at a time.
• C. It requires no sample preparation.
• D. It enables sequence-level STR and mtDNA data in addition to size information.

Answer: (D)

Massively parallel sequencing expands what you can extract from STR analysis by reading the actual DNA sequence at each locus instead of just measuring fragment length. In traditional methods, you infer alleles from size, so different sequences that happen to be the same length look the same on the profile. Sequencing reveals those sequence-level differences, including isoalleles and SNPs within repeats or in the flanking regions, which increases discrimination. It also enables sequencing of the mitochondrial genome, providing mtDNA data in addition to the STR data. In one workflow you get both STR sequences and mtDNA sequences, along with the size information, giving much richer and more actionable information than size-based methods alone. The other statements don’t capture this capability: MPS doesn’t simply run faster with less information, it sequences many loci simultaneously rather than one at a time, and it does require sample preparation for library and sequencing steps.

Massively parallel sequencing expands what you can extract from STR analysis by reading the actual DNA sequence at each locus instead of just measuring fragment length. In traditional methods, you infer alleles from size, so different sequences that happen to be the same length look the same on the profile. Sequencing reveals those sequence-level differences, including isoalleles and SNPs within repeats or in the flanking regions, which increases discrimination. It also enables sequencing of the mitochondrial genome, providing mtDNA data in addition to the STR data. In one workflow you get both STR sequences and mtDNA sequences, along with the size information, giving much richer and more actionable information than size-based methods alone. The other statements don’t capture this capability: MPS doesn’t simply run faster with less information, it sequences many loci simultaneously rather than one at a time, and it does require sample preparation for library and sequencing steps.