Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cytogenetics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources

[The interest of standard and molecular cytogenetics for diagnosis of acute leukemia].

The standard and molecular cytogenetic techniques now belong to the panel of mandatory analyses performed at diagnosis of acute leukemia. Chromosomal abnormalities contribute to define different types of leukemias and present the major advantage to be effective and independent prognostic factors, essential for therapeutic choices. Cytogenetic techniques allowing to identify hyperdiploïdy >50 chromosomes, t(12;21)(p13;q22)/TEL-AML1(ETV6-CBFA2), t(9;22)(q34;q11)/BCR-ABL, 11q23/MLL, t(15;17)(q22;q12-21)/PML-RARalpha, t(8;21)(q22;q22)/AML1-ETO and inv(16)(p13q22)/ CBFbeta/MYH11 are developed. Among the techniques devoted to study genome, cytogenetics is a basic, simple and effective tool for giving a total picture of the genome through karyotype. Maintaining a systematic cytogenetic analysis is essential, not only because cytogenetics now belongs to routine practice but also because it still contributes to better defining morpho-immunologic sub-types of leukemia, to identify new cytogenetic entities and to understand hematopoiesis and leukemogenesis.

Acute Disease↗

FISHing for mechanisms of cytogenetically defined terminal deletions using chromosome-specific subtelomeric probes.

Cytogenetically defined terminal deletions are thought to be a major, yet underappreciated, cause of mental retardation and multiple congenital anomalies. The mechanisms by which terminal deletions arise and are stabilized are not completely understood; although all ends of human chromosomes must have a telomeric cap to be stable. At least three mechanisms exist to maintain chromosome ends with cytogenetically defined terminal deletions: stabilization of terminal deletions through a process of telomere regeneration (termed 'telomere healing'), retention of the original telomere producing interstitial deletions, and formation of derivative chromosomes by obtaining a different telomeric sequence through cytogenetic rearrangement (termed 'telomere capture'). We used chromosome-specific subtelomeric probes and FISH to characterize cytogenetically defined terminal deletions in patients with 1p36 monosomy. Based on the current resolution of these subtelomeric probes, our results indicate that cytogenetically defined terminal deletions of 1p36 are likely to occur through all three mechanisms, although we speculate that the majority of cases were stabilized through telomere regeneration. These results demonstrate the use of chromosome-specific subtelomeric probes as an efficient first step toward uncovering the mechanisms that result in the stabilization of cytogenetically defined terminal deletions.

Chromosome Aberrations↗

Detection of karyotypic aberrations in acute myeloblastic leukaemia: a prospective comparison between PCR/FISH and standard cytogenetics in 140 patients with de novo AML.

In 140 patients with de novo acute myeloid leukaemia (AML) standard cytogenetics were compared with RT-PCR for the detection of t(8;21), t(15;17) and inv(16) and fluorescence in situ hybridization (FISH) for numerical aberrations of chromosomes 7, 8, X and Y. RT-PCR detected 18 cases with t(8;21), 12 with t(15;17) and seven with inv(16). In two cases with t(8;21), two with t(15;17) and four with inv(16) these aberrations had not been detected by standard cytogenetics. There were no false negative PCR results. In 12 patients with these chromosomal changes, standard cytogenetics revealed additional chromosomal aberrations. In 16 patients sole numerical aberrations of the chromosomes 7, 8, X or Y were found by FISH. In these patients the sensitivity of FISH and standard cytogenetics was comparable. In 87 patients no aberrations could be found by PCR and FISH whereas in 24 of these patients standard cytogenetics revealed an abnormal karyotype. These data recommend the combination of standard cytogenetics and molecular techniques to improve the sensitivity for the detection of genetic lesions in AML. Once chromosomal markers have been identified by combined analysis these markers could be used to monitor residual disease during/after chemotherapy, by RT-PCR and/or FISH.

Adult↗

Overview. Cytogenetic analysis in haematology.

Cytogenetic analysis has contributed greatly to our understanding of the nature of leukaemia and lymphoma. Study of these two groups of diseases has revealed general truths about the nature of the neoplastic process. Cytogenetic analysis has demonstrated that haematological neoplasms result from a somatic mutation occurring in a haemopoietic, lymphoid or multipotent stem cell. Complete remission has been related to disappearance of the clone of cells bearing the mutation whereas the occurrence of clonal evolution has often been found to be indicative of increasingly aggressive disease. Cytogenetic analysis of leukaemias and lymphomas has led to the discovery of numerous proto-oncogenes; these generally play a crucial role in proliferation and differentiation of normal cells with a perturbation of their function leading to neoplasia. In addition, cytogenetic evidence has suggested a role for loss of function of cancer-suppressing genes in haematological neoplasms. Cytogenetic analysis has also made major contributions to precise diagnosis and to the assigning of prognosis and, furthermore, by identifying good and poor prognostic groups has improved the management of patients. Good-prognosis patients have been spared unnecessary treatment and, conversely, more intensive treatment for some diseases associated with a cytogenetic abnormality that was previously indicative of a poor prognosis has improved the outcome for these patients.

Chromosome Aberrations↗

Cytogenetic studies in patients on imatinib.

With the introduction of imatinib (Gleevec) (formerly STI571) for the treatment of chronic myeloid leukemia (CML), the various diagnostic methods used to monitor patients must be re-evaluated. Conventional cytogenetics has been the established method for follow-up of patients treated with interferon-alpha (IFN-alpha), and the prognostic value of major and complete cytogenetic remission was demonstrated in a number of studies. In patients on imatinib, these endpoints will likely remain valid, although longer observation is required. Cytogenetic remission as a time-dependent variable may aid risk stratification early on. Clonal evolution, ie, the presence of cytogenetic abnormalities in addition to the Philadelphia (Ph) chromosome, may provide important prognostic information as to the likely response to imatinib in all phases of CML but must be interpreted within the context of other disease characteristics. In some patients, clonal evolution is related to imatinib resistance. Information regarding the impact of specific types of additional cytogenetic abnormalities is still limited. Surprisingly, nonrandom karyotypic abnormalities have also been noted in the Ph-negative cells of some patients in cytogenetic remission. This is a novel phenomenon whose causality and prognostic implications require thorough and systematic evaluation.

Benzamides↗

Implications of germ cell cytogenetic tests in the regulatory process.

As tests for germ cell cytogenetics are not prominent in any regulatory guidelines for assessment of product safety, it was decided to investigate the regulatory implications of germ cell cytogenetics by sending detailed questionnaires to contacts in 12 different regulatory agencies. The questionnaires covered three main sections: the basic principles governing if and when germ cell cytogenetics might be an acceptable alternative to a dominant lethal, heritable translocation or mouse specific locus test; what details of protocol would be desired in a male or female germ cell cytogenetic assay; the presentation of data and the criteria for a valid study and a positive result. Replies were received from seven of those contacted and some of the responses were personal rather than official. They may be summarized as follows. (i) Germ cell tests are rarely requested as a matter of course. Positive results in in vivo somatic cell cytogenetic tests and/or problems indicated in fertility/reproduction studies would suggest to some agencies a need for germ cell tests, but others believe they do not contribute to the assessment of risk for man. (ii) Where germ cell tests are indicated, a dominant lethal test (most often) or heritable translocation test (sometimes) would be seen as helpful in elucidating germ cell effects; the mouse specific locus test is rarely requested due to the large numbers of animals involved and the small number of laboratories with the relevant expertise. (iii) As most widely used germ cell cytogenetic assays do not detect inherited mutations or effects on meiotic processes, they were not readily accepted as alternatives.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Classical and molecular cytogenetic abnormalities and outcome of childhood acute myeloid leukaemia: report from a referral centre in Israel.

The incidence of cytogenetic abnormalities in childhood de novo acute myeloid leukaemia (AML) and its prognostic significance was assessed in an Israeli paediatric referral centre. Cytogenetic analysis was successful in 86 of 97 children (< 20 years of age) diagnosed between 1988 and 2002 with de novo AML. Fluorescence in situ hybridization analysis detected new information in 11 of them, leading to reassignment in cytogenetic group classification. The incidence of the various cytogenetic subgroups was as follows: normal - 9%; t(11q23) - 22%; t(8;21) - 13%; t(15;17) - 8%; inv(16) - 3.4%; abn(3q) - 4.6%; 7/7q-(sole or main) - 5.8%; del(9q)(sole) and +21(sole) - 4.6% each; t(8;16) - 2.3%; t(6;9), t(1;22), +8(sole) - 1.1% each; and miscellaneous - 18%. The overall survival (OS) and event-free survival (EFS) (4 years) for 94 patients treated with the modified Berlin-Frankfürt-Münster (BFM) AML protocols (non-irradiated) were 59.9% (SE = 5%) and 55.7% (SE = 5%), respectively, and for the favourable t(8;21), t(15;17) and inv(16), OS was 60% (SE = 15%), 83% (SE = 15%) and 100% respectively. For the normal group it was 62% (SE = 17%), miscellaneous 64% (SE = 12%), t(11q23) 44.6% (SE = 11%) and of the -7/7q-, del(9q)(sole) or t(6;9), none had survived at 4 years. The incidence of cytogenetic subgroups in the Israeli childhood AML population and their outcome were similar to other recently reported paediatric series. Cytogenetic abnormalities still carry clinical relevance for treatment stratification in the context of modern chemotherapy.

Acute Disease↗

Effect of retinoic acid treatment on cytogenetic remission of chronic myeloid leukaemia.

The cytogenetic responses during the first chronic phase of 11 patients with chronic myeloid leukaemia (CML) treated with all-trans retinoic acid (ATRA) + interferon (IFN) were compared with those of 9 other CML patients treated with IFN alone. Metaphase and interphase cytogenetics and a semi-quantitative polymerase chain reaction were used to evaluate the cytogenetic responses. Two of the 11 patients in the ATRA + IFN group were withdrawn, one of them because of IFN intolerance, and the other because of non-compliance. Of the 9 remaining ATRA + IFN-treated patients 6 exhibited major cytogenetic responses, 3 of which were complete. Of the 9 patients treated with IFN alone, only 2 showed major cytogenetic responses. No severe adverse effects were observed. The preliminary results suggest that the ATRA + IFN combination may be superior in achieving cytogenetic remission in the first chronic phase of CML.

Adult↗

Hematopathologic and cytogenetic findings in imatinib mesylate-treated chronic myelogenous leukemia patients: 14 months' experience.

Imatinib mesylate, an Abl kinase inhibitor, produces sustained complete hematologic responses (CHRs) in chronic myelogenous leukemia (CML) patients, but the sequence and timing of morphologic and cytogenetic changes in CML patients during prolonged imatinib mesylate treatment has not been described. In this report, we document sequential hematologic and bone marrow findings in 19 interferon-refractory/interferon-intolerant chronic phase CML patients on imatinib mesylate for at least 14 months. Patients treated at an effective oral dose (300 to 600 mg per day) were followed with peripheral blood (PB) counts, marrow examination, and cytogenetic studies at 0, 2, 5, 8, 11, and 14 months. By 2 months, 17 of 19 patients achieved CHR; 1 reached CHR by 5 months, and 1 at 11 months. Five of 19 patients developed cytopenias requiring treatment interruption and/or dose reduction, but all were able to continue in CHR on study. In contrast to interferon-alfa treatment, imatinib mesylate-treated CML patients achieved not only CHR but complete morphologic marrow response. Normalization of marrow lagged behind PB response; however, by 8 months, all marrows showed normal or reduced cellularity without morphologic evidence of CML. Eighteen of 19 patients continued in CHR and morphologic marrow remission at 14 months; 1 patient relapsed with chronic phase CML. Although hematologic and marrow responses were uniform, cytogenetic responses were variable. Complete cytogenetic responses occurred in 6 patients, with 4 also in remission by fluorescent in situ hybridization and/or reverse-transcription-polymerase chain reaction. Six of 19 had partial and 7 of 19 no cytogenetic response. Several patients acquired additional clonal cytogenetic abnormalities during therapy, a finding with significant implications for prognosis and laboratory monitoring in imatinib mesylate-treated CML patients.

Adult↗

Morphologic dysplasia in de novo acute myeloid leukemia (AML) is related to unfavorable cytogenetics but has no independent prognostic relevance under the conditions of intensive induction therapy: results of a multiparameter analysis from the German AML Cooperative Group studies.

PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account.

Acute Disease↗

LS-CAP: an algorithm for identifying cytogenetic aberrations in hepatocellular carcinoma using microarray data.

Biological techniques such as Array-Comparative genomic hybridization (CGH), fluorescent in situ hybridization (FISH) and affymetrix single nucleotide pleomorphism (SNP) array have been used to detect cytogenetic aberrations. However, on genomic scale, these techniques are labor intensive and time consuming. Comparative genomic microarray analysis (CGMA) has been used to identify cytogenetic changes in hepatocellular carcinoma (HCC) using gene expression microarray data. However, CGMA algorithm can not give precise localization of aberrations, fails to identify small cytogenetic changes, and exhibits false negatives and positives. Locally un-weighted smoothing cytogenetic aberrations prediction (LS-CAP) based on local smoothing and binomial distribution can be expected to address these problems. LS-CAP algorithm was built and used on HCC microarray profiles. Eighteen cytogenetic abnormalities were identified, among them 5 were reported previously, and 12 were proven by CGH studies. LS-CAP effectively reduced the false negatives and positives, and precisely located small fragments with cytogenetic aberrations.

Algorithms↗

[Current methods of molecular cytogenetics in pre- and postnatal diagnosis of chromosome aberrations].

Progress in prevention of chromosome aberrations is due to utilization of molecular cytogenetic diagnostic methods. The purpose of this trend of clinical cytogenetics is development and utilization of new highly effective methods for analysis of chromosome aberrations. Molecular cytogenetic methods (fluorescent in situ hybridization-FISH) are used for pre- and postnatal identification of chromosome aberrations in mentally retarded children and congenital diseases. These studies are carried out after classical cytogenetic analysis, if it proves to be of no avail. FISH diagnosis pre- and postnatally detects autosomal trisomy, gonosome aneuploidy (including mosaic forms), marker chromosomes, structural chromosome aberrations, including fragile X chromosome syndrome. Rapid (15-30 min) FISH with an original collection of centromere, telomere, and site-specific DNA probes (plasmid, cosmid, PAC and YAC clones) is recommended for molecular cytogenetic diagnosis. FISH diagnosis is an effective complex of methods for pre- and postnatal identification of chromosome aberrations and a necessary supplement to classical cytogenetic diagnosis. Molecular studies of chromosome aberrations are significant for theoretical and applied studies, for they help detect patients with specific chromosome syndromes from a vast group of children with undifferentiated mental retardation and congenital diseases.

Aneuploidy↗

Correlation between cytogenetic abnormalities and disease characteristics in multiple myeloma: monosomy of chromosome 13 and structural abnormalities of 11q are associated with a high percentage of S-phase plasma cells.

BACKGROUND AND OBJECTIVES: Cytogenetic studies in multiple myleoma (MM) are limited by the difficulties in obtaining metaphases that can be investigated and few studies have analyzed the relationship between cytogenetics and clinical disease characteristics. The aim of our study was to analyze the recurrent cytogenetic changes in MM and to correlate them with clinical and biological characteristics including the percentage of S-phase plasma cells (PCs). DESIGN AND METHODS: Chromosomal abnormalities were analyzed in 86 patients with MM. In all patients, two types of cultures (5 d culture with interleukin-4 and unstimulated 72 h culture) were used for cytogenetic analysis. DNA content analysis (ploidy and cell cycle analysis) together with the most relevant clinical and biological disease features were studied. RESULTS: Cytogenetic analysis was successful in 72 of the 86 patients (84%). Forty-seven patients (65%) had an abnormal karyotype. The most frequent trisomies involved chromosomes 3, 5, 9, 11, 15, 19, 22, 1, 7, 17, 18, and 21, and monosomies affected chromosomes 13 and 8, while structural changes involved chromosomes 1, 11, 14q32, 4p16 and 16q22-23. Patients with abnormal karyotype displayed a poor performance status, advanced stage, anemia and a high percentage of bone marrow plasma cells. In addition, MM patients with -13/13q- and 11q abnormalities showed a significantly higher proportion of S-phase PCs (p=0.02). INTERPRETATION AND CONCLUSIONS: In summary, our study shows a relationship between unfavorable cytogenetics (-13/13q-/11q abnormalities) and a high percentage of S-phase PCs, a well-known adverse prognostic factor.

Aged↗

Association of specific cytogenetic aberrations with mdr1 gene expression in adult myeloid leukemia and its implication in treatment outcome.

BACKGROUND AND OBJECTIVES: Cytogenetics and mdr1 expression are established prognostic factors for treatment outcome in adult acute myeloid leukemia (AML). The association, however, between specific cytogenetic aberrations and mdr1 expression has not yet been examined in a large cohort of patients. DESIGN AND METHODS: We therefore looked for mdr1 gene expression at diagnosis within specific cytogenetic aberrations in 331 previously untreated adult patients with de novo or secondary AML (not including t(15;17)) entered into the German SHG AML96 treatment trial. RESULTS: The proportion of mdr1 positive blast probes was significantly higher in patients with aberrant karyotypes than in those with normal karyotypes (39% vs. 15%; p<0.001). Looking at specific cytogenetic aberrations significantly more mdr1 positive AML patients were found within t(8;21), +8, +21, del(7q), del(5q), -7, abn(3q) and multiple aberrations. In contrast, no patient with inv(16) was positive for mdr1. Only 26% of mdr1 positive patients with aberrant karyotypes achieved complete remission (CR) whereas 54% of the mdr1 negative counterparts did so (p=0.002). Furthermore, within abn(11q), +21, +22, -5 or abn(3q) no mdr1 positive patient reached CR, whereas the mdr1 negative counterparts had CR rates comparable to the CR rate of patients with a normal karyotype. This was most impressive in mdr1 negative patients with multiple aberrations achieving a CR rate of 63% (p=0.019). In the multivariate analysis age, disease status and mdr1 expression were the strongest independent predictors for induction treatment failure. INTERPRETATION AND CONCLUSIONS: The correlation described here between mdr1 gene expression and some cytogenetic aberrations might explain the prognostic divergence of such cytogenetic aberrations in different AML treatment trials due to the amount of mdr-drugs used within the protocols.

Adolescent↗

Quantitative reverse transcription polymerase chain reaction should not replace conventional cytogenetics for monitoring patients with chronic myeloid leukemia during early phase of imatinib therapy.

BACKGROUND AND OBJECTIVES: Imatinib is the new standard drug treatment for patients with chronic myelogenous leukemia (CML). Quantitative reverse transcription-polymerase chain reaction (qPCR) for detection of BCR-ABL transcripts is frequently used for monitoring patients in addition to or instead of conventional cytogenetics, although its place in the overall diagnostic framework is not yet clear. In this study, we compared qPCR and conventional cytogenetics for monitoring of patients during the early phases of imatinib therapy. DESIGN AND METHODS: One hundred and seventeen patients treated with imatinib for CML in chronic or accelerated phase were prospectively followed with qPCR and karyotyping. Comparisons were made between both methods and between qPCR results from bone marrow and peripheral blood. To determine the prognostic impact of qPCR and cytogenetics during the early phase of imatinib treatment on subsequent cytogenetic response and progression-free survival (PFS), a multivariate model was generated that included established prognostic baseline variables. RESULTS: We found a significant correlation between the proportion of Philadelphia (Ph) chromosome-positive metaphases and qPCR in the bone marrow and peripheral blood. Low qPCR values after 3 months of therapy were correlated with major cytogenetic response (MCyR) at 6 months and PFS at 2 years. However, in multivariate analysis, the cytogenetic response at 3 months emerged as the only independent parameter predictive of MCyR at 6 months and PFS at 2 years. INTERPRETATION AND CONCLUSIONS: Our data suggest that conventional karyotyping should remain the standard method for following patients on imatinib during the early phases of therapy.

Adult↗

Hematologic and cytogenetic findings in eleven chronic myelogenous leukemia patients treated with imatinib mesylate at a tertiary care hospital.

OBJECTIVE: To evaluate the response of Imatinib mesylate in patients with myeloid leukemia in chronic accelerated and blast phase. PATIENTS AND METHODS: Eleven patients with established diagnosis of chronic myeloid leukemia were treated with Imatinib mesylate. Adverse events were documented with regular follow ups. Hematological and cytogenetic responses were assessed according to established criteria. Patients with zero percent Philadelphia positive metaphases were labeled as complete cytogenetic response while patients with 1% to 35% Philadelphia positive metaphases were termed as partial responders. RESULTS: Of 11 cases there were 7 males and 4 females with a mean age of 39.5 years and median age 51 years (range 21-69). Male to female ratio was 7:4. Median follow-up was 34 weeks (range 8-78). Four patients were in blast crisis, 1 in accelerated phase and remaining six patients were in chronic phase. All patients achieved hematological response. Cytogenetic response was present in six patients, 3 were responders and the remaining were non responders. Two patients achieved complete cytogenetic response and one patient had partial cytogenetic response. Both patients with complete cytogenetic response relapsed in twelve weeks time. CONCLUSION: Imatinib mesylate is a drug with curative potential and can be used as a first line drug in the management of CML, however at present the cure rate is unknown.

Adult↗

Interphase cytogenetic analysis detects minimal residual disease in a case of acute lymphoblastic leukemia and resolves the question of origin of relapse after allogeneic bone marrow transplantation.

We used in situ hybridization with a probe for the X chromosome to study interphase cells of bone marrow and peripheral blood specimens from a male patient with acute lymphoblastic leukemia characterized by hyperdiploidy, including trisomy X. In a posttreatment bone marrow specimen, which was interpreted as a regenerating bone marrow morphologically and which demonstrated a normal karyotype cytogenetically, trisomy X was found in 16 of 1,000 interphase cells. This finding indicated the presence of leukemic cells that were undetected by conventional morphologic and cytogenetic techniques (ie, minimal residual disease). Cytogenetic studies of a relapse specimen obtained after a sex-mismatched bone marrow transplant showed only a normal female karyotype in each of 40 metaphase cells, suggesting that the relapse occurred in donor cells. However, interphase analysis demonstrated trisomy X in more than 80% of interphase cells and indicated that the relapse was of the original clone and was not a transformation of donor cells. This case illustrates that interphase analysis can be useful as an adjunct to conventional cytogenetic analysis in the detection of minimal residual disease and in the analysis of interphase cells that are not accessible to routine cytogenetic methods. It also illustrates that previously reported instances of relapse of leukemia in donor cells could have been incorrect if supported by cytogenetic data alone.

Adult↗

Southern technique and cytogenetics are complementary and must be used together in the evaluation of Ph1, M-BCR positive chronic myeloid leukemia (CML) patients treated with alpha interferon (IFN-alpha).

Cytogenetic analysis is the gold standard for the follow-up of CML patients. The sensitivity of cytogenetics is fairly similar to that of Southern detection of M-BCR rearrangement (5%); this last technique has the potential advantage of being independent of cell division and yield of metaphases. IFN alpha treatment can induce lack of growth of hemopoietic precursors and poor yield of metaphases has been observed. For this reason we decided to study the grade of concordance and complementarity between analysis of karyotype and detection of M-BCR rearrangement of Southern blot. We studied 43 Ph1 positive, M-BCR positive pre-BMT CML patients (48 samples) treated with IFN alpha 2a. Karyotype was done on bone marrow cells by direct method, culture, and banding. Southern technique was performed onto DNA from peripheral blood leukocytes treated with BgIII (and Xbal if necessary) and hybridized with the universal probe (Ph1/bcr-3, Transprobe 1) labelled with dCTP32. A highly significant association between both tests was obtained. Of 48 samples analyzed, 34 were evaluable by both methods and 28 gave the same result for both tests. The concordance between the tests was good (kappa index: 0.63). Of total samples 27.1% was not evaluable by cytogenetics; this figure was 31.2% in samples from patients who were previously in complete cytogenetic response. All of the specimens not evaluable by karyotyping were evaluable by Southern. One sample was not analyzable by Southern but it was evaluable by cytogenetic analysis. The information obtained by Southern technique was clinically relevant, and decisions were made according to its results. We conclude that both tests show a significant association and a good concordance, although they are not interchangeable. Cytogenetic and molecular studies are complementary and must be employed together in CML patients treated with alpha-interferon.

Blotting, Southern↗