WGA DNA Library Preparation Using Built-In Sequencing Adapters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for generating massively parallel sequencing libraries from Whole Genome Amplification (WGA) products, such as DRS-WGA, are laborious and expensive, and existing protocols require multiple enzymatic steps, making them inefficient for low-pass whole-genome sequencing and genome-wide copy-number profiling, especially when using platforms like Illumina.
Innovation Solution
A streamlined method involving a single PCR cycle with primers containing different sequencing adapters at each end, followed by purification steps, allows for the generation of a double-strand DNA library suitable for Illumina platforms, eliminating the need for complex buffer systems and multiple enzymatic steps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple enzymatic steps and complex protocols are used for library generation from WGA products, then sequencing library quality is improved, but process complexity and cost increase
Solution Approach 1:
The patent combines multiple separate enzymatic steps (digestion, end repair, A-tailing, adapter ligation) into a single streamlined PCR-based protocol. The method uses primers with built-in adapter sequences that directly amplify WGA products to generate sequencing-ready libraries, eliminating the need for sequential enzymatic treatments and reducing the process to essentially one main reaction step followed by purification.
Solution Approach 2:
The patent employs universal PCR primers that contain all necessary adapter sequences for Illumina sequencing. These primers serve multiple functions simultaneously: they amplify the WGA product, add platform-specific adapters, and enable direct sequencing without requiring separate adapter ligation steps. This multi-functional approach simplifies the workflow while maintaining library quality.
2Adaptability or versatility
If standard Illumina workflow steps (digestion, fragmentation, end repair, A-tailing, adapter ligation) are performed, then library compatibility with Illumina platforms is improved, but labor and time requirements increase
Solution Approach 1:
The patent incorporates all necessary adapter sequences directly into the PCR primers before the amplification reaction. This preliminary inclusion of adapter sequences eliminates the need for subsequent adapter ligation steps and ensures Illumina platform compatibility is achieved during the amplification process itself, saving significant time and labor.
Solution Approach 2:
The patent extracts and eliminates unnecessary intermediate steps from the standard Illumina workflow. By using PCR primers that already contain the required adapter sequences, the method removes the need for separate digestion, end repair, A-tailing, and adapter ligation steps, keeping only the essential amplification and purification steps.
3Stability of the object's composition
If DRS-WGA is used for whole genome amplification, then amplification uniformity is improved, but downstream library preparation complexity increases
Solution Approach 1:
The patent merges the advantages of DRS-WGA (uniform amplification) with a simplified PCR-based library preparation approach. By using primers that contain built-in adapter sequences, the method maintains the uniformity benefits of DRS-WGA while eliminating the complexity of subsequent enzymatic processing steps, creating a seamless transition from amplification to sequencing-ready library.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method simplifies the library preparation process, ensuring reproducible and high-quality genome-wide copy-number profiling with reduced costs and labor, suitable for analyzing minute samples like single cells or FFPE biopsies.
Implementation Method 1
a) a primary WGA DNA library is provided, comprising fragments comprising a 5' sequence section (5SS), a middle sequence section (MSS), and a 3' sequence section (3SS), reverse complementary to the 5' sequence section; b) a single PCR cycle is performed on the primary WGA DNA library using at least one first primer (1PR), resulting in a first primer extended WGA DNA library; c) a single PCR cycle is performed on the first primer extended WGA DNA library using at least one second primer (2PR), resulting in a first and second primer extended WGA DNA library
Implementation Method 2
at least one first primer (1PR), comprising a first primer 5' section (1PR5S) and a first primer 3' section (1PR3S), wherein the first primer 5' section (1PR5S) comprises at least one first sequencing adapter (1PR5SA) and the first primer 3' section (1PR3S) hybridizes to the 3' sequence section (3SS)
Data Source
AI summary
There is disclosed a method of generating a massively parallel sequencing library comprising the steps of :a) providing a primary WGA DNA library (pWGAlib), including fragments comprising a WGA library universal sequence adapter; b) performing a single PCR cycle on the pWGAlib using a first primer (1PR) comprising from 5′ to 3′ a first sequencing adapter (1PR5SA) and a first primer 3′ section (1PR3S) hybridizing to the reverse complementary of the WGA library universal sequence adapter; c) performing a single PCR cycle on the on the product of step b) using a second primer (2PR) comprising from 5′ to 3′ a second sequencing adapter (2PR5SA) different from the 1PR5SA, and a second primer 3′ section (2PR3S) hybridizing to the WGA library universal sequence adapter reverse complementary; d) amplifying by PCR the product of step c) using a third primer comprising the 1PR5SA and a fourth primer comprising 2PR5SA.