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Sequencing-by-Synthesis (SBS)

Definition

The Illumina detection paradigm: reversibly fluorescent 3'-blocked nucleotides are incorporated one cycle at a time into clonally amplified clusters on a flow cell; laser imaging at each cycle reads the incorporated base by its colour. SBS generates short reads (150-300 bp) at high throughput, distinguishing it from Sanger's long-read (700-1000 bp) single-molecule extension.

Related terms

2',3'-Dideoxynucleotide Triphosphate (ddNTP)
A nucleotide analogue lacking the 3'-hydroxyl group present in normal dNTPs. When incorporated by DNA polymerase into a growing chain, it prevents...
Big Dye Terminator (BDT) V3.1
Applied Biosystems' (now Thermo Fisher Scientific's) commercial cycle sequencing kit using four spectrally distinct dichlororhodamine dyes coupled to the four ddNTPs. The...
Cycle Sequencing
A Sanger sequencing format using a thermostable DNA polymerase and repeated denaturation-annealing-extension cycles (typically 25-35 cycles). Produces exponentially more termination products from...
EMPOP (ENBISI Mitochondrial Population Database)
The ENFSI-curated reference database of forensic-grade mtDNA haplotypes used to estimate the frequency of a given control-region profile in a specified population....
Phred Quality Score
A logarithmic estimate of base-calling error probability (Phred Q = -10 log10 P). Q20 = 1% error rate; Q30 = 0.1% error...
rCRS (Revised Cambridge Reference Sequence)
The standard reference sequence for the human mitochondrial genome (NC_012920.1, 16,569 bp), used as the coordinate system for reporting all forensic mtDNA...

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