Cerebellar ataxia-hypogonadism syndrome is a very rare autosomal recessive neurodegenerative disorder characterized by the combination of progressive cerebellar ataxia with onset from early childhood to the fourth decade, and hypogonadotropic hypogonadism (delayed puberty and lack of secondary sex characteristics). Cerebellar ataxia-hypogonadism syndrome belongs to a clinical continuum of neurodegenerative disorders along with clinically overlapping disorders such as ataxia-hypogonadism-choroidal dystrophy syndrome (see this term).

Hypogonadotropic hypogonadism is characterized by reduced function of the gonads (testes in males or ovaries in females) and results from the absence of the gonadal stimulating pituitary hormones: follicle stimulating hormone (FSH) and luteinizing hormone (LH).