Cytogenetics investigation in childhood chronic myeloid leukemia.

Cytogenetics investigations, mostly from peripheral blood, were carried out in 30 children with CML. Amongst a sample of 30 patients, 18 had chronic myeloid leukemia of adult variety (ACML), while the remaining 12 children had the juvenile type of chronic myeloid leukemia (JCML). Sixteen (88.9%) out of the 18 patients suffering from ACML tested positive for the classical Philadelphia chromosome translocation t(9; 22). Of the remaining two ACML patients, one tested positive for t(9; 13; 22) while no visible chromosomal changes were observed in the other patient. The activity of Nucleolar Organizer Region (NOR) was significantly reduced in 11 (61.1%) of the 18 patients suffering from ACML, when compared to that of 21 normal healthy controls. Ten out of the 12 patients suffering from JCML had normal karyotypes, while monosomy 8 and 21 q deletion were seen in the remaining two patients respectively. Amongst the 30 CML patients, chromosomal abnormalities were observed in 19 patients. Variant Philadelphia chromosome translocation (9; 13; 22) and monosomy B were observed in ACML and JCML, respectively. In two ACML patients, cytogenetic studies were helpful in diagnosis of the disease.

Karyotyping of at risk fetuses by cordocentesis in advanced gestation.

Fetal blood obtained by cordocentesis was cultured to obtain rapid karyotypes of fetuses at risk during the late second trimester. Ninety nine fetal blood samples were studied for chromosomal abnormalities. The commonest indications for the procedure were abnormalities detected on ultrasonography (47.7%), and previous child with Down syndrome. Analysis of the 67 successful cultures showed four (5.9%) karyotypic abnormalities. The technique proved helpful in the obstetrical management of at risk fetuses.