Chronic myelocytic leukemia. Chromosome studies of a patient and his nonleukemic identical twin

✍ Scribed by J. Bauke

• Publisher: John Wiley and Sons
• Year: 1969
• Tongue: English
• Weight: 475 KB
• Volume: 24
• Category: Article
• ISSN: 0008-543X
• DOI: 10.1002/1097-0142(196909)24:3<643::aid-cncr2820240333>3.0.co;2-6

✦ Synopsis

T h e chromosome constitution of peripheral blood cells and bone marrow cells was studied in a 31-year-old man with chronic myelocytic leukemia a n d his normal identical twin. Evidence for their identity includes similar physical appearance, identical blood group antigens a n d serum factors, similar fingerprint patterns, and phenylthiocarbamide tasting. A typical Philadelphia chromosome was found in the patient. It was absent in bone marrow metaphases of the nonleukemic twin, 8% years after diagnosis of leukemia in the other twin. This supports the view that the Philadelphia chromosome is not inherited. To obtain more information about the concordance rate of monozygotic twins, all affected twin pairs should b e reported, and long-term follow-up observations are needed.

NTIL 1967 FOUR SETS OF IDENTICAL TWINS

U associated with chronic myelocytic leukemia (CML) have been reported.6-7,9918 In each pair a Philadelphia (Phl) chromosome could be demonstrated only in the leukemic twin. T h e Phl chromosome was absent in all bone marrow cells from nonleukemic co-twins. Therefore, it was assumed to be an acquired postzygotic abnormality. However, recently Weinerl7 and Tokuhata et a1.16 described 2 families with high incidence of CML and Phl chromosome, suggesting an inherited tendency to develop a Phl chromosome.

This communication reports the clinical and cytogenetic findings in another set of identical twins, one having CML.

CASE REPORT

Leukemic twin: T h e proband twin (F. S.) is a 31-year-old man. At 12 years of age the patient had the onset of a seizure disorder, which persists to the present. In 1951, the From the Abteilung fiir Haematologie, Zentrum fiir