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What is an Oligo?

Integrated DNA Technologies (IDT) manufactures custom products made up of short strands of DNA or RNA called oligonucleotides (often abbreviated to oligos). The word “oligo” comes from Greek, and it means “few.” To understand how oligos are useful, it is important to know a bit about DNA itself.

DNA is “the blueprint for life” and encodes instructions for life’s processes. DNA is a complex, long, thin molecule made up of two strands that hydrogen-bond together. Each of the strands is made from nucleotides that have four possible building blocks called bases. These bases are called adenine (A), cytosine (C), guanine (G), and thymine (T), and the precise order of these bases is a code for information. The bases hold the two strands together, where G connects to C and T connects to A. The hydrogen bonds therefore attract the strands together like pieces of a puzzle, where only complementary regions can remain together in a stable structure. The interaction is not permanent, and naturally occurring enzymes or heat can easily separate the two strands. In living organisms, DNA strands can be millions of bases long and therefore contain huge amounts of information. This is responsible for the vast complexity and diversity of life.

The way that one strand of DNA specifically interacts with a complementary strand of DNA allows scientists to use short DNA strands called oligonucleotides as research tools. For example, a short synthetic piece of DNA (usually around 20 bases long) can find its complementary sequence in a complex mixture of millions of unrelated pieces of DNA. Historically, since such synthetic single-stranded DNA (ssDNA) fragments were only about 20 bases long, they were given the name “oligo.”  Today, however, “oligos” are available in lengths of up to several hundred bases. No formal conventions exist for the maximum length of a DNA fragment with this name.

The word “oligo” usually still refers to ssDNA strands such as those which IDT manufactures.  However, today, IDT also produces double-stranded DNA (dsDNA) fragments such as gBlocks™ Gene Fragments, eBlocks™ Gene Fragments, and gBlocks HiFi Gene Fragments.   Although dsDNA fragments such as these are not usually called “oligos,” there are, again, no strict rules for the use of this term.  Meanwhile, RNA, which is naturally single-stranded, is another molecule type that can be obtained for research as an “oligo.” IDT is a supplier of high-quality ssRNA oligos as well.

What are Oligos Used For?

Scientists often start their research knowing the DNA or RNA sequence for the organism that they are interested in studying. Given a known sequence, investigators can easily design an oligo for their research that can be used to perform a variety of tasks, such as DNA sequencing, amplification of DNA segments with PCR, analyzing gene expression, genotyping, changing DNA sequence information with CRISPR-Cas genome editing, and many other applications. DNA and RNA oligos designed for each of these applications can be conveniently ordered from IDT. Living systems do not discriminate DNA or RNA that is synthesized chemically from DNA or RNA taken directly from an organism. Therefore, IDT custom-made oligonucleotides can substitute in research experiments for naturally-occurring DNA or RNA from any organism for any naturally-occurring process. 

IDT manufactures oligos using proprietary oligonucleotide synthesis machines designed and built  in-house. IDT has refined the process to the point where an order can be manufactured and delivered to the researcher the next day. Customers range from small university labs of only a few scientists to global pharmaceutical companies. 

IDT is the industry leader in the competitive field of custom oligonucleotides. The company has reached this position by maintaining the highest standards of quality, service, and technical expertise.

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