Endocrinal description of two Chinese Kennedy's disease pedigrees

Kennedy's disease (KD), also known as X-linked spinal and bulbar muscular atrophy (SBMA), is caused by the expansion of cytosine-adenine-guanine (CAG) repeats in the first exon of the androgen receptor (AR) gene. KD is a late-onset neural-endocrinal disease that is characterized by the degeneration of motor neurons in the brainstem and spinal cord. In addition, partial androgen insensitivity is an important manifestation of KD. Here, we report two Chinese KD pedigrees that reveal the clinical and genetic manifestations and fully elaborate the endocrinal characteristics of KD patients. The proband in pedigree 1 was referred to an endocrinologist for gynaecomastia and sexual dysfunction. A gene analysis of this patient revealed that there were 53 CAG repeats in the AR gene. A family survey identified an additional two KD patients in pedigree 1. The proband in pedigree 2 was diagnosed by a neurologist and did not have gynaecomastia or sexual dysfunction. A family survey identified an additional subclinical patient, and both patients exhibited partial androgen insensitivity at a hormonal level. We therefore suggest that a family survey and hormone tests should be routinely performed in KD patients and that physicians should increase their understanding of the different symptoms of KD to achieve correct diagnoses in affected patients.