spinobulbar muscular atrophy
(SBMA) an X-linked, adult-onset disorder with degeneration of lower motor neurons in the brainstem and spinal cord, characterized by distal limb amyotrophy and bulbar signs such as atrophy and fasciculations of the tongue and dysphagia, as well as androgen insensitivity with gynecomastia, testicular atrophy, and oligospermia. It is a triplet repeat disorder with expansion of CAG repeats in the AR gene (locus: Xq11-q12), which encodes the androgen receptor. Called also Kennedy disease.
Medical dictionary.
2011.