Synthetic Biology
Support and Educational Content

Libraries of double-stranded DNA fragments

Accelerate development of recombinant genes or proteins 

With gBlocks® Gene Fragments Libraries, IDT expands its synthetic biology products line by offering 500 bp gBlocks Gene Fragments containing up to 18 consecutive N or K bases (see Definitions box, below). The regions of the gene fragments that are ordered as fixed sequences containing  A, G, C, or T bases are sequence-verified, while a proprietary manufacturing method ensures homogeneous distribution of the variable N or K bases.

gBlocks Gene Fragments Libraries are the ideal tool to generate up to 418 sequence variations that could be used for a variety of functional screenings of nucleotide or peptide variants in numerous scientific applications. In addition, depending on the number of variations tested, gBlocks Gene Fragments Libraries can reduce the cost of an individual sequence to a fraction of $1 (USD) per construct.


N and K are standard IUBMB (International Union of Biochemistry and Molecular Biology) identifiers for unspecified or incompletely specified nucleotide bases, where N can be an A, G, C, or T base; and K is either a G or T base.

For more information, or to order gBlocks Gene Fragments, go to

Additional reading

Site-directed mutagenesis—improvements to established methods—Site-directed mutagenesis techniques have relied primarily on PCR and standard cloning methods. Read about some of the common cloning methods used for mutagenesis and how double-stranded DNA fragments (gBlocks Gene Fragments) can save you both time and money.

Mutagenesis using gBlocks® Gene Fragments—Citation summary: Learn how just 3 synthetic, high fidelity, double-stranded gBlocks Gene Fragments used to mutate 18 different sites over the entire exon 7, 1039 bp sequence.

Generating Quick Constructs for Intracellular Vesicular Transport Studies—Research profile: gBlocks Gene Fragments provide rapid and cheap access to new types of functional and structural elements for constructing novel biological modules and cascades to better understand the tethering complexes and transcription-regulating complexes critical to intracellular vesicular transport.

Improving Vaccine Development—Research profile: A directed, molecular evolution process employed by the biopharmaceutical company, Altravax, uses in vitro DNA recombination to generate large libraries of recombined, chimeric DNA sequences that express potential vaccine candidates. IDT gBlocks Gene Fragments have proved instrumental in this high throughput technology.

A Next Generation Understanding of Immune Response—Research profile: Scientists in the Church Laboratory at Harvard Medical School used assembly PCR of antibodies with gBlocks® Gene Fragments and PCR-amplified DNA to study the immune system's response to patients receiving flu vaccinations.

Author: Hans Packer, PhD, is a scientific writer at IDT.

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gBlocks® Gene Fragments

Double-stranded DNA up to 3,000 kb—great for easy gene construction, CRISPR genome editing, and more.

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