The incidences of trisomy 8, trisomy 9 and D20S108 deletion in polycythaemia vera: an analysis of blood granulocytes using interphase fluorescence insitu hybridization
Nb. Westwood et al., The incidences of trisomy 8, trisomy 9 and D20S108 deletion in polycythaemia vera: an analysis of blood granulocytes using interphase fluorescence insitu hybridization, BR J HAEM, 110(4), 2000, pp. 839-846
We have used interphase fluorescence in situ hybridization (IFISH) to detec
t trisomy 8, trisomy 9 and 20q deletion in circulating granulocytes from pa
tients with polycythaemia vera (PV). Out of 64 PV patients, 15 (23%) exhibi
ted an abnormality. Two patients had trisomy 9, three had trisomy 8 and 10
patients had hemizygous deletion of D20S108 (a locus in the 20q common dele
ted region). Aberrant nuclei ranged from 10% to 80% in these 15 cases. Ther
e was no correlation between the presence of a marker and sex, age, interva
l between presentation and IFISH analysis, neutrophil or platelet count or
therapy. Conventional marrow cytogenetic karyotype results were available i
n 23 cases and there was concurrence between these and blood IFISH in 16 ca
ses (13 normal and three with 20q/D20S108 deletion by both methods). Three
patients with D20S108 deletion by IFISH were normal by previous marrow cyto
genetic testing and four cases with 20q deletion by previous marrow cytogen
etics had normal blood granulocytes according to IFISH. Thus, we confirm th
at trisomies 8 and 9 and deletion of 20q are diagnostically useful markers
of PV. IFISH analysis of blood granulocytes is a practical method for detec
ting these markers, but as an adjunct to, not as a substitute for, conventi
onal marrow cytogenetics.