Cerebellar ataxia and hypergonadotropic hypogonadism in two kindreds. Chance concurrence, pleiotropism or linkage?

Two kindreds with Marinesco-Sjögren's syndrome in three sibships are described. In five of the six affected, but in none of the unaffected sibs, a hypergonadotropic hypogonadism was observed. In one of the kindreds a high degree of inbreeding was revealed, and inbreeding likely also existed in the other kindred. The two families were not related. Marinesco-Sjögren's syndrome is known to be a distinct clinical entity, governed by autosomal recessive inheritance, and this also applies to hypergonadotropic hypogonadism. Several heredo-degenerative nervous disorders are accompanied by a hypogonadotropic hypogonadism, which is believed to be secondary to the neurological disorder, as in traumatic paraplegia. A hypergonadotropic hypoganadism cannot readily be explained in this way. We consider genetic linkage between two independent disorders as the most likely explanation for the observed concurrence.