AR and Adult onset: Spinal and bulbar muscular atrophy (SBMA), or Kennedy’s disease, is an X-linked, adult-onset neuromuscular disease caused by a CAG (cytosine-adenine-guanine) trinucleotide repeat expansion encoding a polyglutamine (polyQ) tract in the androgen receptor (AR) (1) and affecting 1 in 50,000 men worldwide (2).