Genomic DNA Extraction

Genomic DNA isolation and genomic DNA extraction are related terms that refer to generation of purified genomic DNA from a given starting material such as cells or tissue. Let’s talk about each term in a bit more detail.

What is genomic DNA extraction?

Genomic DNA extraction is the process of releasing chromosomal DNA from the cellular matrix in which it is contained. Genomic DNA extraction requires a robust disruption method to open the nuclei and cell walls (if applicable); it usually involves adding a compatible detergent as well as mechanical shearing.

Following genomic DNA extraction is isolation, in which the proteins, cell membranes, and other cellular materials are removed yielding a purified genomic DNA sample.

Methods for genomic DNA isolation

Three general methods for genomic DNA isolation are common, and each is based on a different biochemical principle. Selection of a method is based on the throughput required, equipment available in the lab, and how the purified genomic DNA will be used.

Organic extraction and precipitation

Genomic DNA isolation by organic extraction involves the addition of phenol and quanidine isothiocyanate to separate the DNA and proteins into different organic phases. Organic extraction is a low-cost method and, with advanced reagents such as DNAzol, is a straightforward method requiring very little equipment.


DNA binds to silica (aka glass fibers) under high-salt conditions and can be released under low-salt conditions. Silica-containing columns provide an easy way to bind, wash, and elute purified genomic DNA from multiple clarified cell lysates in parallel.

Columns are designed to flow buffers through centrifugation, vacuum, or gravity. PureLink Genomic DNA Mini Kits use spin column technology and work in a microcentrifuge for easy prep of up to 18 samples at a time. Spin plates provide the same isolation technology in a high-throughput, automation-friendly format.

Paramagnetic beads

In this method, paramagnetic (attracted to magnet) beads are added to the sample, and genomic DNA binds to the beads. Using a strong magnet, the beads are held in place while removing unwanted material. After washing, the genomic DNA is eluted from the beads in water or a low-salt buffer. The bead-based method, used in MagMAX multi-sample DNA isolation and related kits, is scalable and automation compatible.

Simplify your genomic DNA extraction process with Thermo Fisher Scientific kits and reagents

Genomic DNA extraction kits contain all of the reagents needed to get you from sample to purified DNA. Thermo Fisher Scientific offers Genomic DNA extraction kits in your choice of formats for specific sample types:

For Research Use Only. Not for use in diagnostic procedures.