Abstract
Association patterns of acrocentric chromosomes in 3032 cells from chromosomally normal parents of regular mongols (nondisjunctional trisomy 21) and normal controls were studied by the Giemsa banding technique. In each group, chromosome No. 21 was found to be involved in satellite association more frequently than other acrocentric chromosomes. The most frequently seen association was between No. 21 and 22. However, no difference was shown between the parental test group and the normal controls in regard to these frequencies. These results render less tenable the proposed linkage between satellite association and the etiology of mongolism.