From the time we are conceived and through old age, genetic mutations accumulate in all our tissues, eluding the body’s typically efficient DNA repair machinery and potentially affecting our health ...

Two months later, Gould began to experience a strange cascade of symptoms. His ankles swelled to the width of his calves. The right side of his face became so bloated that he could not open his eye.

The mutation in the huntingtin (HTT) gene, which causes the incurable, dominantly inherited Huntington’s disease, was identified decades ago, following one of the most closely watched disease gene ...