46,X,i(Xq)/45,X mosaicism with gonadal dysgenesis associated with 21p-

This paper presents a female patient with a clinical picture of gonadal dysgenesis and the chromosome constitution with a monocentric isochromosome of one X and a marker chromosome 21 with deleted short arm. The proband's father and other members of the family suffered from Huntington's chorea and each of them possessed the deleted chromosome 21. Our case supports the idea that minor chromosome aberrations may increase the inclination for the development of unbalanced recombinant offsprings.