Team:Judd UK/Pages/Description

Description

Over 2 billion people worldwide in both MEDCs and LEDCs are affected by anaemia; mainly infants and pregnant women. Iron deficiency symptoms include lethargy, heart conditions, pale skill and even reduced cognitive ability, so a straightforward way to test whether one has abnormal amounts of it would be greatly beneficial. Additionally, many countries give out iron tablets prophylactically to pregnant women, breast feeding women and to children, whether they are anaemic or not (because anaemia is such an issue). Side effects of overdoses of iron are similarly harmful so to be able to home-test and know that iron supplements are not required would be extremely beneficial. Our iGEM project is to create a home testing kit for detecting iron levels, to warn people with abnormal concentrations of this essential mineral. The kits will be in the form of slips of paper, which are actually cell-free systems. These include all the necessary cellular components in cell-free extracts and our genetic construct which are embedded into the paper and freeze dried. They are easily stored and distributed at a stable room temperature and when necessary can be activated by rehydration. A key aspect of our project is that to make it even easier to measure iron concentrations we will be testing saliva because it is unobtrusive and easy to obtain. In order to react to different iron levels our construct will be promoted by the AceB gene, which is usually involved in carbon source management, but more importantly is regulated by FUR, a transcriptional repressor of genes involved in iron homeostasis. In the presence of Fe2+ ions this protein dimerises which allows linkage to a FUR binding site to inhibit mRNA transcription of the downstream gene. In order so that an increase in iron leads to an increase in transcription we will use an inverter. We will use a chromoprotein as our reporter to produce a vibrant blue colour in response to iron that can be seen clearly without additional equipment. Different levels of iron will result in different levels of transcription of the chromoprotein so our device will be semi-quantitative.