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

Abstract

Two kindreds with Marinesco-Sjoegren''s syndrome in 3 sibships are described. In 5 of the 6 affected, but in none of the unaffected sibs, a hypergonadotropic hyogonadism was observed. In one of the kindreds a high degree of inbreeding was revealed, and inbreeding likely also existed in the other kindred. The 2 families were not related. Marinesco-Sjoegren''s syndrome is known to be a distinct clinical entity, governed by autosomal recessive inheritance; this also applies to hypergonadotrophic 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 hypogonadism cannot readily be explained in this way. Genetic linkage between 2 independent disorders is probably the most likely explanation for the observed concurrence.