Study shows how mutant huntingtin protein triggers brain cell death In 1993, scientists discovered that a single mutated gene, HTT, caused Huntington's disease, raising high hopes for a quick cure. Yet today, there's still no approved treatment. One difficulty has been a limited understanding of how the mutant huntingtin protein sets off brain cell death, says neuroscientist Srinivasa Subramaniam, Ph.D., of Scripps Research, Florida. In a new study published in Nature Communications on Friday, Subramaniam's group has shown that the mutated huntingtin protein slows brain cells' protein-building machines, called ribosomes. The ribosome has to keep moving along to build the proteins, but in Huntington's disease, the ribosome is slowed. The difference maybe two, three, four-fold slower. That makes all the difference."