High-fidelity single-stranded DNA (ssDNA) fragments designed for your homology-directed repair (HDR) of CRISPR-mediated genome editing, in vitro transcription, and more.
Includes your ssDNA fragment of interest and the complementary strand, delivered dry in separate tubes. Fragments are normalized to 3 µg final yield. Both strands will be delivered for each sequence entry.
|Megamer™ ssDNA Fragments—Sense + Antisense, 201–500 bases||$820.00 USD|
|Megamer™ ssDNA Fragments—Sense + Antisense, >500 bases||$1.70 USD / base|
Includes your ssDNA fragment of interest, without the complementary strand, delivered dry. Fragments are normalized to 3 µg final yield.
|Megamer™ ssDNA Fragment, 201–500 bases||$615.00 USD|
|Megamer™ ssDNA Fragment, >500 bases||$1.40 USD / base|
Megamer ssDNA Fragments are single-stranded genomic blocks for research applications such as homology-directed repair of CRISPR-mediated genome editing, in vitro transcription, and more. Megamer fragments are 201–2000 bases in length and are generated from clonally derived DNA. Megamer ssDNA Fragments are sequence-verified via next generation sequencing and are typically shipped within 20 business days*. They are composed of A, T, G, and C nucleotides only.
* The time required to manufacture a Megamer ssDNA Fragment is dependent on many factors and may exceed the estimated delivery time.
The Alt-R HDR Donor Block and Megamer products are both intended to generate CRISPR-mediated insertions. Alt-R HDR Donor Blocks are chemically modified dsDNA repair templates while Megamer Single-Stranded DNA Fragments are long ssDNA repair templates. Megamer fragments are also chemically modified templates, however, their modification is different than that of HDR Donor Blocks. Due to the differences in manufacturing, Megamers are limited in yield (3 µg standard) and can be more costly. Alt-R HDR Donor Blocks are available at larger yields that are typically required for cell culture work (3 or 10 µg standard) and offer a more cost-effective solution. While both products can be used to create CRISPR knock-ins, several differences in repair outcomes have been observed between dsDNA and ssDNA repair templates.
First, ssDNA innately has a lower risk of non-homologous end joining (NHEJ) mediated insertion compared to unmodified dsDNA. IDT’s proprietary modifications help mitigate that risk when using an Alt-R HDR Donor Block. Second, long ssDNA repair templates can result in incomplete HDR insertions. This does not occur frequently with dsDNA templates such as Alt-R HDR Donor Blocks.
Finally, HDR (homology-directed repair) outcomes may be impacted by foreign DNA of a particular system. While successful HDR has been observed using both products in most systems tested, the ideal donor template may vary with the application and the cell line or system of choice.
IDT has a free, online codon optimization tool available through our SciTools™ Web Tools suite that you can use to perform codon optimization before ordering your oligonucleotide.
To optimize, simply paste in an amino acid or nucleotide sequence and select your desired expression host. If you need additional assistance, contact us.
Sequence Information is secure and confidential at IDT. Please see our Confidentiality Statement for more information. All online ordering steps, including sequence entry and your choice of parameters, are also secure and protected.
We screen the sequence of every gene, gene fragment, and Megamer™ ssDNA fragment order we receive to (1) identify any regulated and other potentially dangerous pathogen sequences, and (2) verify that IDT’s gene customers are legitimate scientists engaged in beneficial research.
IDT is among the five founding members of the International Gene Synthesis Consortium (IGSC) and helped to create the IGSC’s Harmonized Screening Protocol. The Harmonized Screening Protocol describes the gene sequence and customer screening practices that IGSC member companies employ to prevent the misuse of synthetic genes. IDT takes the steps set out in the Harmonized Screening Protocol to screen the sequences of ordered genes and the prospective customers who submit those orders.
For more information about the IGSC and the Harmonized Screening Protocol, please visit the website at www.genesynthesisconsortium.org.
In October 2010, the United States government issued final Screening Framework Guidance for Providers of Synthetic Double-Stranded DNA, describing how commercial providers of synthetic genes should perform gene sequence and customer screening. IDT and the other IGSC member companies supported the adoption of the Screening Framework Guidance, and IDT follows that Guidance in its application of the Harmonized Screening Protocol. For more information, please see 75 FR 62820 (Oct. 13, 2010), or https://federalregister.gov/a/2010-25728.
*RUO—For research use only. Not for use in diagnostic procedures. Unless otherwise agreed to in writing, IDT does not intend for these products to be used in clinical applications and does not warrant their fitness or suitability for any clinical diagnostic use. Purchaser is solely responsible for all decisions regarding the use of these products and any associated regulatory or legal obligations.