DNA fragmentation

DRAFT

This page is a work in progress and is subject to change at any moment.

Most sequencing platforms require DNA fragments of specific sizes:

• Enzymatic fragmentation: Employs restriction enzymes or non-specific endonucleases to cleave DNA at defined sites or randomly.
• Mechanical shearing: Includes methods like sonication or hydrodynamic shearing, which produce random fragments.
• Tagmentation: A more recent method that combines fragmentation and adapter ligation in a single step using transposase enzymes.

The choice of fragmentation method depends on the sequencing platform and the desired fragment size distribution.

Size Selection

To ensure optimal sequencing performance, DNA fragments must be within a specific size range:

• Gel electrophoresis: Fragments of the desired size are excised from agarose gels.
• Bead-based methods: Magnetic beads with size-selective binding properties are used to isolate fragments of interest.
• Microfluidic systems: Automated platforms that can precisely select fragments based on size.