Cytogenetically cryptic AML1-ETO and CBF beta-MYH11 gene rearrangements: incidence in 412 cases of acute myeloid leukaemia.
The rearrangements t(8;21)(q22;22) and inv(16)(p13q22) are two of the most frequently seen in acute myeloid leukaemia (AML), accounting for 8% and 4% of cases respectively. Detection of these abnormalities is important for disease management as both are associated with good responses to conventional chemotherapy and prolonged disease-free survival. Recent reports using reverse transcriptase polymerase chain reaction (RT-PCR) suggest that significant proportions of AML cases without a visible t(8;21) or inv(16) show expression of an abnormal fusion gene transcript and, consequently, they could not be detected using conventional cytogenetic analysis alone. We present here a four centre study involving 412 cases of AML screened using both standard cytogenetics and RT-PCR for AML1-ETO and CBF beta-MYH11. We detected a cytogenetic t(8;21) in 31 out of 412 (7.5%) cases and an inv(16) or t(16;16) variant in 27 out of 412 (6.6%) cases. RT-PCR detected only two cases (0.5%) of cryptic t(8;21) and no instances of cryptic inv(16). Both cryptic t(8;21) cases had the classic M2 FAB morphology for this type of disease. Our data concur with the established FAB type distribution of the rearrangements and indicate that cryptic t(8;21) and inv(16) may be much less frequent than reported elsewhere.
Rowe
D
D
School of Biochemistry and Genetics, University of Newcastle upon Tyne, UK. david.rowe@ncl.ac.uk
Cotterill
S J
SJ
Ross
F M
FM
Bunyan
D J
DJ
Vickers
S J
SJ
Bryon
J
J
McMullan
D J
DJ
Griffiths
M J
MJ
Reilly
J T
JT
Vandenberghe
E A
EA
Wilson
G
G
Watmore
A E
AE
Bown
N P
NP
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D007446:Chromosome Inversion; D002874:Chromosome Mapping; D002885:Chromosomes, Human, Pair 16; D002891:Chromosomes, Human, Pair 21; D002898:Chromosomes, Human, Pair 8; D005260:Female; D015321:Gene Rearrangement; D005819:Genetic Markers; D006801:Humans; D015994:Incidence; D007223:Infant; D007951:Leukemia, Myeloid / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014178:Translocation, Genetic
D005819:Genetic Markers