Automated DNA Library Prep | Whole‑Genome Re‑sequencing of Human Blood gDNA

Whole-genome re-sequencing of human samples is the core technology for mining genomic variants and powering precision-medicine programs such as tumor-susceptibility gene screening, hereditary-disease diagnosis and pharmacogenomics. Blood gDNA library construction has traditionally relied on manual operation, which suffers from low throughput, poor reproducibility and operator-dependent error — shortfalls that large clinical cohorts can no longer tolerate.

This application note presents an optimized, fully automated blood gDNA re-sequencing library-construction method on the MGISP-960 platform using the Hieff NGS™ OnePot Pro DNA Library Prep Kit V4 (12972ES). End-to-end automation eliminates manual deviation, improves construction efficiency and uniformity, and delivers a stable, controllable workflow for standardized high-throughput re-sequencing.

Background and Pain Points

Clinical genomics raises the bar for library construction well beyond what a bench-top workflow can deliver:

•  Cohort scale: clinical and population studies run hundreds to thousands of blood samples; manual preparation is the throughput bottleneck.

•  Variant-calling accuracy: consistent insert sizes and low batch variation are prerequisites for reliable SNV / InDel detection.

•  Sample economy: manual transfers lose precious clinical material and waste high-value reagents.

•  Traceability: manual records complicate the quality audits expected in clinical laboratory environments.

Application Scenarios

The automated blood gDNA workflow underpins the main streams of human precision medicine.

Figure 1. Application landscape covered by the automated human blood gDNA library-construction workflow.

The Automated Workflow

The complete protocol runs on the MGISP-960 with the OnePot Pro DNA Library Prep Kit V4 (12972ES) and MGI-compatible UDB adapters. Manual touchpoints are limited to sample loading, adapter dilution (10 μM → 5 μM) and final library collection.

Figure 2. Automated human blood gDNA library-preparation workflow on the MGISP-960 (MGI library).

Reagent List for the Experiment

Category	Cat.No.	Product name
DNA Library Preparation	12972ES	Hieff NGS™ OnePot Pro DNA Library Prep Kit V4
Magnetic Beads	12601ES	Hieff NGS™ DNA selection Beads (Superior Ampure XP alternative)
Quantification	12642ES	1× dsDNA HS Assay Kit dsDNA qubit
Adapters	13350ES	Hieff NGS™ Unique Dual Barcode Primer Kit for MGI, Set 1 (plate format)
Automation Consumables	83560ES / 83672ES / 83130ES	0.2 mL 96-well PCR plates (white, full skirt) / 96-deep-well plates (U-bottom, 1.3 mL) / 250 μL filtered sterile tips
Sealing	83624ES	qPCR pressure-sensitive sealing film (scraper included)
User-Supplied Materials	—	Absolute Ethanol

Pre-Experiment Preparation

•  Equilibrate DNA Selection Beads to room temperature for at least 30 minutes and resuspend fully before deck loading.

•  Prepare fresh 80% ethanol for all bead washes.

•  Dilute the UDB adapter stock from 10 μM to 5 μM (manual pre-step, keep on ice).

•  Load one 96-sample consumable set and confirm deck layout, liquid volumes and tip integrity.

•  Verify gDNA integrity (high-molecular-weight, A260/280 ~1.8) before the run.

Experimental Tips

Sample & input

•  100 ng blood gDNA per sample is the validated starting point; keep input consistent across the plate.

•  Avoid repeated freeze-thaw cycles of blood gDNA — sheared input broadens the insert-size distribution.

Bead-based purification & size selection

•  0.68×/0.20× dual selection reproducibly delivers ~350 bp inserts suited to standard short-read re-sequencing.

•  Avoid over-drying beads after ethanol washes; cracked pellets reduce elution recovery.

Adapter handling & PCR

•  Dilute adapters manually before the run and keep on ice; unique dual barcode adapters prevent index hopping.

•  6 PCR cycles are sufficient for 100 ng input and keep duplication low.

Automation & QC

•  Run scripts exactly as specified in the 12972ES IFU — plate geometry and liquid classes are validated together.

•  Accept finished libraries at 29–45 ng/μL (Qubit) with a sharp ~350 bp band on agarose or Qsep before pooling.

Experimental Conditions and Results

 

Case results (spot-check, Qubit 4.0):

All six libraries fell between 29 and 45 ng/μL with a total yield of 818–1,260 ng; agarose-gel electrophoresis showed insert sizes of approximately 350 bp, meeting sequencing-ready specifications.

Figure 3. Library concentration and total yield across the validated human blood gDNA run (n = 6, 28 μL elution).

Figure 4. Human blood gDNA library size distribution with a sharp single peak at ~350 bp.

Analysis of Experimental Results

Libraries were constructed from gDNA isolated from human blood using the enzymatic fragmentation library‑prep kit 12972ES. High library yield and tight fragment‑size distribution were achieved, satisfying standard quality‑control requirements for whole‑genome re‑sequencing.