Chromosomal Studies in Erythroleukemia and Chronic Erythremic Myelosis

Chromosome studies were performed in four cases of erythroleukemia, in one case of acute erythremic myelosis and in one case of chronic erythremic myelosis. Abnormalities were encountered in all of these cases. No consistent patterns were found although clonal lines could be detected in three cases. A common feature in five of the cases was a variable degree of involvement of the chromosomes of the G group (presence of G monosomy in two cases, Ph¹-like chromosome in two cases, and a slight reduction in size of a small acrocentric chromosome in 40 per cent of the metaphases in the case of chronic erythremic myelosis). C trisomy was present in one case. These findings indicate that the involvement of groups G and C may represent an important feature of the Di Guglielmo syndrome and suggest a close relationship of this disorder with other myeloproliferative diseases.