IPSWICH, MA, USA — Detecting a specific DNA sequence outside of the laboratory, without bulky equipment or even electricity, may seem unlikely. However, astronauts aboard the International Space Station (ISS) did just that using a technique developed by New England Biolabs (NEB).

For the first time, astronauts 250 miles above Earth successfully tested a novel DNA detection method that changes color in the presence of a target DNA sequence, in only 30 minutes. The method, developed by NEB, is called colorimetric loop-mediated isothermal amplification (cLAMP). It works through a clever combination of an inexpensive pH dye and less of the buffer that scientists typically use during polymerase chain reaction (PCR). A change from pink to yellow indicates the presence of a predetermined DNA or RNA sequence. 

“One major hurdle to DNA-based diagnostics in outer space — particularly those based on PCR — is the need for specialized equipment, which can present significant logistical challenges. With limited resources and challenging working environments associated with deep space travel, astronauts will need diagnostics that are simple and easy-to-use,” said Nicole Nichols, Group Leader, DNA Polymerase Development at NEB and co-investigator of the experiment. 

“The robustness of colorimetric LAMP in zero gravity opens up a whole new set of possibilities, including the ability to test for viruses, health markers, or even food and environmental organisms, granting a degree of self-sufficiency needed for life and survival in space,” Nichols said.

Here on Earth, this technique could be instrumental in improving healthcare in remote regions of the world. For example, river blindness, the second most common cause of blindness due to infection, is normally detected through either microscopic examination or PCR detection of the Onchocerca volvulus parasite, both of which require equipment and procedures that can be cumbersome for researchers that need a quick diagnosis out in the field. 

“The colorimetric LAMP assay is poised to help those who need to work without electricity and use reagents that are cost effective,” said Nichols. “NEB’s parasitology research group recently tested a cLAMP assay directly on skin snips from African patients with river blindness and found that it was more sensitive in detecting the parasite than PCR and conventional microscopy.”

LAMP, which is a single tube technique that can make large amounts of DNA at a constant temperature, obviates the need for expensive thermocyclers used in conventional nucleic acid amplification methods like PCR. However, NEB scientists have modified the LAMP method by adding a colorimetric component that exploits a natural phenomenon during DNA amplification. 

“LAMP produces large quantities of protons when DNA from a sample is amplified. However, these protons are masked by the buffer used in a typical LAMP reaction,” explains Nathan Tanner, staff scientist at NEB, and one of the developers of the colorimetric LAMP assay. 

“By removing the buffer from the reaction, we demonstrated that the accumulation of protons significantly changes pH levels. This change can be visualized by adding a pH-sensitive colorimetric dye, such as our pink to yellow indicator. We’ve taken this principle and developed it into a stable formulation, which is commercially available for a wide range of diagnostic assay developers to enable field-friendly, point-of-care tests,” Tanner said.

The colorimetric LAMP assay conducted on the ISS was part of an experiment designed by Julian Rubenfein, from New York’s Stuyvesant High School. Rubenfein was the 2016 winner of Genes in Space™, a national competition that challenges students in grades 7-12 to design experiments that solve real-life space exploration problems through DNA analysis. Rubenfein’s proposal was centered around the examination of telomere dynamics in outer space and involved two sets of experiments that were flown on board the ISS — the colorimetric LAMP experiment and a more traditional PCR, also conducted using NEB’s reagents. Both experiments were enabled by a portable thermocycler aboard the ISS designed by miniPCR™. 

The Genes in Space competition was founded by miniPCR and Boeing and is sponsored by Math for America, the Center for the Advancement of Science in Space, NEB, and FedEx.

More information about the experiment 


Learn more about colorimetric LAMP

Learn more about the Genes in Space Competition

 

About New England Biolabs
Established in the mid 1970s, New England Biolabs, Inc. (NEB) is the industry leader in the discovery and production of enzymes for molecular biology applications and now offers the largest selection of recombinant and native enzymes for genomic research. NEB continues to expand its product offerings into areas related to PCR and qPCR, gene expression, sample preparation for next generation sequencing, synthetic biology, glycobiology, epigenetics and RNA analysis. Additionally, NEB is focused on strengthening alliances that enable new technologies to reach key market sectors, including molecular diagnostics development. New England Biolabs is a privately held company, headquartered in Ipswich, MA, and has extensive worldwide distribution through a network of exclusive distributors, agents and seven subsidiaries located in Canada, China, France, Germany, Japan, Singapore and the UK. More information about New England Biolabs