The 2025 Cambridge iGem team wins Gold

The Cambridge iGEM team won a Gold Medal at the 2025 iGEM Grand Jamboree. Their project ‘CamiRa’ aimed to develop a cheap, fast and accessible tool for on-farm crop diagnosis.

The International Genetically Engineered Machine (iGEM) is the world’s largest synthetic biology competition, in which university students work in labs over the summer to solve real-world problems by repurposing or engineering biological systems. In 2025 alone, thousands of students from over 400 universities worldwide presented their work at the Grand Jamboree in Paris.

Meet the Team

This year’s iGem team was interdisciplinary and international, comprising nine Cambridge undergraduates: Kim Anjarwalla (1^st year Natural Sciences), Molly Dorricott (1^st year Natural Sciences), Alexander Gillan (1^st year Natural Sciences), Amitan Joseph (1^st year Engineering), Kelda Lee (1^st year Natural Sciences), Cassandra Lui (1^st year Natural Sciences), Darren Sim (1^st year Natural Sciences), Steven Sun (1^st year Natural Sciences), and Paul Vongtanakiat (1^st year Natural Sciences).

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The 2025 Cambridge iGem Team outside Churchill College. From left to right: Molly Dorricott, Amitan Joseph, Alexander Gillan, Kelda Lee, Darren Sim, Steven Sun, Kim Anjarwalla, Paul Vongtanakiat and Cassandra Lui.

CamiRa (Crop assessment by miRNA analysis)

Current crop diagnostic methods rely on visual or lab analysis; the former can be inaccurate and occurs too late, since the plant has already shown a phenotype, while the latter is expensive and not accessible to many small-scale farmers in poorer countries and remote locations. What if someone could detect stress in a plant caused by nutrient deficiencies or pathogen infection before the plant shows any symptoms, in a cheap, fast, and accessible way?

The 2025 Cambridge iGem team aimed to tackle this question by developing CamiRa (Crop assessment by miRNA analysis). Because specific miRNAs are upregulated in plants during stress responses (e.g., miR-399 is upregulated when a plant lacks phosphate) before the appearance of a phenotype, the team leveraged this to develop their diagnostic system.

The diagnostic system consists of a paper disc with components for Rolling Circle Amplification (RCA) and a circular DNA ssDNA probe containing the complementary sequence to the miRNA. RCA uses the target miRNA as the primer to replicate the DNA sequence on the circular probe, creating a long stretch of DNA (Figure 1).

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Figure 1: Rolling circle amplification (RCA) can be initiated by miRNA binding to a circular ssDNA probe, acting as a primer for the DNA polymerase.

The extended DNA was designed to include a guanine-rich sequence that forms a non-canonical secondary structure called a G-quadruplex, which was then detected with the fluorescent dye Thioflavin T using a black box and an app the team developed (Figure 2).

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Figure 2: Fluorescence caused by Thioflavin T bound to G-quadruplex structures formed from an extended rolling circle amplification (RCA) product.

Given that farmers do not own standard lab equipment, such as pipettes or ultracentrifuges, and to avoid the use of hazardous chemicals, the team developed a safe, easy-to-use method for miRNA extraction from plant tissue. The method is an adaptation of the isopropanol RNA extraction method, designed to be accessible to farmers. The extraction kit includes a hand centrifuge, pestle, and a ‘Syringe Pipette’ and can extract miRNA from plant leaves (Figure 3).

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Figure 3: The hand centrifuge, pestle, and the ‘Syringe Pipette’ designed for the safe and accessible RNA extraction method.

In summary, the team developed a proof-of-concept method for on-farm crop diagnosis that is cheap, fast, and easy to use.