Source: Chemical & Engineering News
A new class of therapies based on transfer RNA could treat forms of cystic fibrosis, muscular dystrophy, genetic epilepsies, and more
When Daniel Fischer cofounded Tevard Biosciences in 2017, he wasn’t trying to bet on the next hot RNA technology. His interest was more personal. His daughter Natasha has Dravet syndrome, a rare form of epilepsy caused by a genetic glitch in a type of sodium channel. This protein conducts electrical signals that brain cells use to communicate. For years, the glitch tormented Natasha with more than 40 small seizures every night. Fischer and his wife took turns staying up with her. “We didn’t sleep,” he says.
Several medications have helped reduce the frequency of Natasha’s seizures, but her disease has taken a cognitive and physical toll on her. Fischer has made it his life’s work to find a cure for Dravet. He explored the possibility of using gene therapy or gene editing—technologies that were dominating headlines for their ability to tackle other rare genetic disorders. But scientists told him those approaches would be difficult to implement for Dravet. Instead, a newfangled idea called transfer RNA (tRNA) therapy seemed like it might be the answer.
Transfer RNA, or tRNA, as it’s known to biologists, helps cells assemble proteins from amino acids by translating the nucleotide code of messenger RNA (mRNA). Each tRNA molecule reads a trio of nucleotides called a codon, which represents instructions for adding a particular amino acid to a protein. The tRNA then earns its name by transferring the corresponding amino acid to the cell’s protein-making machinery, known as the ribosome. This process repeats along the length of the mRNA strand until the ribosome runs into a stop codon, a special trio of nucleotides that marks the end of the protein-making instruction manual. The ribosome’s job is done.