British scientists have developed a new strain of Escherichia coli with a genetically recoded genome. By reducing the number of codons, scientists have freed part of the DNA code, creating the potential to design and use novel amino acids not found in nature. In 2019, scientists created the Syn61 strain with 61 codons, which required 18,000 DNA modifications. The earlier Syn61 strain is already used to produce more reliable medicines. It marks an important step forward in the fields of synthetic biology and genetic engineering.