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PubMed2003

Phylogenetic analysis by 16S rDNA gene sequence comparison of avian taxa of Bisgaard and characterization and description of two new taxa of Pasteurellaceae.

AIMS: Characterization and classification of members of Pasteurellaceae isolated from birds by extended phenotypic characterization and 16S rDNA gene sequence comparison. METHODS AND RESULTS: A total of 95 avian isolates were subjected to extended phenotypic characterization. Thirteen bacterial strains selected from main phenotypic clusters and isolated from parrot, parakeet, budgerigar, partridge, pheasant, chicken, duck, hawk and gull were subsequently characterized by 16S rDNA gene sequencing. Eight of the sequenced strains were classified with six taxa of Bisgaard of which two (34 and 40) have not been published before, and the properties of four others (14, 22, 26 and 32) changed upon the characterization of these new isolates. Of the remaining strains, one was identified as a phenotypic variant in maltose and dextrin of Pasteurella gallinarum another as a trehalose positive variant of taxon 3 of Bisgaard. The remaining three strains sequenced were not closely related to existing taxa of Pasteurellaceae. However, they were found to belong to the Avian cluster with 92-97% 16S rDNA gene sequence similarity. CONCLUSION: The study allowed the classification of bacteria isolated from birds by the integrated use of extended phenotypic characterization and 16S rDNA gene sequence analysis. Only the application of 16S rDNA gene sequencing allows a correct identification of variant strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The description of new taxa within the bacterial family Pasteurellaceae will subsequently allow additional isolates of these taxa to be identified and improve the diagnosis and epidemiological understanding of bacteria causing disease in birds.

Animals↗

PubMed1995

[Revised WHO classification and new developments in diagnosis of central nervous system tumors].

In recent years there has been considerable progress in brain tumor neuropathology. Several new diagnostic entities have been recognized, subclassification schemes have been modified, and new concepts on the histogenesis and cell biology of brain tumors have emerged. In 1993, a revised WHO classification of brain tumors was published by an international committee. This article summarizes the pertinent new aspects. As novel tumor entities, the central neurocytoma, the dysembryoplastic neuroepithelial tumor (DNT), desmoplastic infantile ganglioglioma (DIG) and pleomorphic xanthoastrocytoma (PXA) have been included. Several histopathological variants of meningiomas have been added of which only the papillary meningioma and the atypical meningioma are characterized by an increased rate of recurrence. Meningeal hemangiopericytomas and hemangioblastomas are classified as tumors of non-meningothelial origin. The glioblastoma multiforme, which had previously been listed as an embryonal tumor, is now recognized as an astrocytic glioma. Immunohistochemistry has greatly advanced the practical diagnosis and classification of brain tumors. There are specific markers for all normal and neoplastic cell types except for oligodendroglioma cells. The prognosis of and therapeutic approaches to brain tumors greatly depend on histopathological grading. The WHO proposes four tumor grades, i.e., I, II, III, and IV. As a rule, grades I and II tumors are viewed as benign or semi-benign neoplasms and grades III and IV tumors as malignant. There are attempts to use new biological parameters for the grading of brain tumors. Antibodies to proliferation-associated proteins reflect tumor growth. Molecular genetic approaches to tumor-associated genes and gene loci are particularly promising new tools for the future.

Biomarkers, Tumor↗

PubMed2000

Classification of adhesive domains in the Plasmodium falciparum erythrocyte membrane protein 1 family.

The Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) family of cytoadherent proteins has a central role in disease from malaria infection. This highly diverse gene family is involved in binding interactions between infected erythrocytes and host cells and is expressed in a clonally variant pattern at the erythrocyte surface. We describe by sequence analysis the structure and domain organization of 20 PfEMP1 from the GenBank database. Four domains comprise the majority of PfEMP1 extracellular sequence: the N-terminal segment (NTS) located at the amino terminus of all PfEMP1, the C2, the Cysteine-rich Interdomain Region (CIDR) and the Duffy Binding-like (DBL) domains. Previous work has shown that CIDR and DBL domains can possess adhesive properties. CIDR domains grouped as three distinct sequence classes (alpha, beta, and gamma) and DBL domains as five sequence classes (alpha, beta, gamma, delta, and epsilon). Consensus motifs are described for the different DBL and CIDR types. Whereas the number of DBL and CIDR domains vary between PfEMP1, PfEMP1 domain architecture is not random in that certain tandem domain associations--such as DBLalphaCIDRalpha, DBLdeltaCIDRbeta, and DBLbetaC2--are preferentially observed. This conservation may have functional significance for PfEMP1 folding, transport, or binding activity. Parasite binding phenotype appears to be a determinant of infected erythrocyte tissue tropism that contributes to parasite survival, transmission, and disease outcome. The sequence classification of DBL and CIDR types may have predictive value for identifying PfEMP1 domains with a particular binding property. This information might be used to develop interventions targeting parasite binding variants that cause disease.

Amino Acid Motifs↗

PubMed1997

Red cell acetyl cholinesterase and plasma cholinesterase activity and genetic variants of plasma cholinesterase in northwest Indian adults.

The plasma cholinesterase (PChE) and red cell acetyl cholinesterase (AChE) activities are indicators of exposure to organophosphates. We studied their distribution in unexposed Northwest Indian adults by measuring them in 120 men and 111 women by Ellman's and Kalow's method, respectively. We also determined genetic variability of plasma cholinesterase in 193 subjects (male = 111, female = 82). The mean +/- (SD) AChE levels in population, men and women, were 34.97 +/- 13.66, 35.05 +/- 12.42, 34.88 +/- 14.89 nmol/mg Hb/min, whereas PChE was 0.448 +/- 0.173, 0.435 +/- 0.163, 0.462 +/- 0.183 ku/l, respectively. When compared for sex, no significant difference could be found for red cell AChE and PChE activity. However, on 2-way analysis of variance (ANOVA) adjusted for age classification, the levels of both AChE and PChE were significantly higher in groups above the age of 30 years as compared to below 30 years (t = 3.08, p < 0.01, t = 2.82, p < 0.05), respectively. Seven genetic variants of PChE could be detected in males, whereas in females 6 genetic variants were found.

Acetylcholinesterase↗

PubMed1997

Basaloid squamous cell carcinoma of the esophagus: diagnosis and prognosis.

BACKGROUND: Basaloid squamous cell carcinoma (BSCC) is a recently recognized, poorly differentiated variant of squamous cell carcinoma (SCC), which is located predominantly in the upper aerodigestive tract. METHODS: In this study, clinical and pathologic parameters of 17 BSCCs and 133 typical SCCs of the esophagus that underwent potentially curative resection (no distant metastases, no residual tumor) were compared. In addition, light microscopic, electron microscopic, and immunohistochemical features of BSCC were investigated, to determine whether this type of carcinoma could be differentiated from other poorly differentiated carcinomas of the esophagus. RESULTS: Light microscopic study showed that BSCC was composed of relatively small tumor cells, arranged in solid lobules with abundant comedo-type necrosis. BSCC was almost invariably accompanied by areas of concomitant typical SCC, foci of squamous cell differentiation, and/or severe squamous cell dysplasia or carcinoma in situ of the adjacent mucosa. Ultrastructurally, BSCC inconsistently showed features of squamous cell differentiation. Immunohistochemically, BSCC displayed poor reactivity for antibodies against wide-range cytokeratins and cytokeratin subtypes that are typical of squamous cell epithelia (cytokeratin 13 and cytokeratin 14). Infrequently, expression of Leu7, smooth muscle actin, and S-100 protein was found. In comparison with typical SCC, the characteristic features of BSCC were older patient age, higher proliferative activity (MIB-1 labelling index), and higher apoptotic indices. No differences were found with regard to pT classification, pN classification, tumor size, blood vessel invasion, lymphatic vessel invasion, neural invasion, or patient gender. Moreover, no differences in overall survival rates were found. CONCLUSIONS: BSCC is a distinct histopathologic variant of SCC, characterized by a poor degree of differentiation and high proliferative activity. However, after potentially curative resection, the prognosis of patients with BSCC of the esophagus does not differ from that of patients with typical SCC.

Actins↗

PubMed2006

Subsequent suicide mortality among emergency department patients seen for suicidal behavior.

OBJECTIVES: To determine whether suicide mortality rates for a cohort of patients seen and subsequently discharged from the ED for a suicide-related complaint were higher than for ED comparison groups. METHODS: This was a nonconcurrent cohort study set at a university-affiliated urban ED and Level 1 trauma center. All ED patients 10 years and older, with at least one ED visit between February 1994 and November 2004, were eligible. ED visit characteristics defined the cohort exposure. Patients with visits for suicide attempt or ideation, self-harm, or overdose (exposed) were compared with patients without these visits (unexposed). Exposure classification was determined from billing diagnoses, E-codes (E950-E959), and free-text searching of the ED tracking system data for suicide, overdose, and spelling variants. Emergency department patient data were probabilistically linked to state mortality records. The principal outcome was suicide death. Suicide mortality rates were calculated by using person-year (py) analyses. Relative rates (RR) and 95% confidence intervals (95% CIs) were calculated from Cox proportional hazards models. RESULTS: Among the 218,304 patients, the average follow-up was 6.0 years; there were 408 suicide deaths (incidence rate [IR]: 31.2 per 100,000 py). Males (IR: 48.3) had a higher rate than females (IR: 13.5; RR: 3.6; 95% CI = 2.8 to 4.6). A single ED visit for overdose (RR: 5.7; 95% CI = 4.5 to 7.4), suicidal ideation (RR: 6.7; 95% CI = 5.0 to 9.1), or self-harm (RR: 5.8; 95% CI = 5.1 to 10.6) was strongly associated with increased suicide risk, relative to other patients. CONCLUSIONS: The suicide rate among these ED patients is higher than population-based estimates. Rates among patients with suicidal ideation, overdose, or self-harm are especially high, supporting policies that mandate psychiatric interventions in all cases.

Adolescent↗

PubMed2002

[Classification of broncho-pulmonary cancers (WHO 1999)].

Tumour classification systems provide the foundation for tumour diagnosis and patient therapy and a critical basis for epidemiological and clinical studies. This updated classification was developed with the aim to adhere to the principles of reproducibility, clinical significance, and simplicity in order to minimize the number of unclassifiable lesions. Major changes in the revised classification as compared to the previous one (WHO 1981) include the addition of two pre-invasive lesions to squamous dysplasia and carcinoma in situ: atypical adenomatous hyperplasia (AAH) and diffuse idiopathic pulmonary neuroendocrine cell hyperplasia. Another change is the subclassification of adenocarcinoma: the definition of bronchioloalveolar carcinoma has been restricted to non-invasive tumours. There has been substantial evolution of concepts in neuroendocrine lung tumour classification. Large cell neuroendocrine carcinoma (LCNEC) is now recognized as a histologically high-grade non-small cell carcinoma showing histopathological features of neuroendocrine differentiation as well as immunohistochemical neuroendocrine markers. The large cell carcinoma class has been enriched with several variants, including the large cell neuroendocrine carcinoma and the basaloid carcinoma, both of which have a poor prognosis. Finally, a new class has been defined called carcinoma with pleomorphic, sarcomatoid, or sarcomatous elements, which gathers a number of proliferations characterized by a spectrum of epithelial to mesenchymal differentiation. Immunohistochemistry and electron microscopy are invaluable techniques for diagnosis and subclassification, but our intention was to render the classification simple and practical to every surgical laboratory so that most lung tumours can be classified by light microscopic criteria.

Adenocarcinoma↗

PubMed2026

Bayesian Integration of Tumor Mutational Signatures and Somatic Features Refines Pathogenicity Assessment of Germline Mismatch Repair Variants.

Variants of uncertain significance (VUS) in mismatch repair (MMR) genes represent a persistent bottleneck in germline interpretation for Lynch syndrome, creating a critical opportunity to leverage tumor biology to refine pathogenicity assessment. Although tumor features such as microsatellite instability (MSI) and immunohistochemistry (IHC) are routinely evaluated, they are typically interpreted separately from germline classification, and their quantitative contribution within ACMG/AMP frameworks remains poorly defined. We therefore analyzed paired germline and tumor sequencing data from 1110 tumors across 1073 patients with colorectal or endometrial cancer to determine whether mismatch repair-deficient (MMR-d) mutational signatures can be quantitatively integrated into Bayesian germline variant interpretation. Using COSMIC single-base substitution signatures, tumors were classified as MMR-d or MMR proficient, and an empirically derived likelihood ratio (LR) quantified the association between MMR-d signatures and pathogenic germline MMR variants. The presence of an MMR-d signature increased the likelihood of an underlying pathogenic germline MMR variant approximately eightfold (LR ≈ 8; log10 LR ≈ 0.90), whereas its absence provided moderate-to-strong benign evidence (LR ≈ 0.156; log10 LR ≈ -0.81). Applying this integrative framework to 45 germline MMR VUS, joint modeling of tumor mutational signatures with additional somatic and variant-level evidence resulted in clinically significant reclassification of 38 (84.4%) variants, including three reclassified as pathogenic or likely pathogenic and 35 as likely benign. A total of 16 downgraded variants were independently downgraded by Invitae. These findings demonstrate that tumor mutational signatures can be formally incorporated into Bayesian germline interpretation, transforming tumor data into quantitative pathogenicity evidence and offering a principled strategy to reduce VUS burden in hereditary cancer genetics.

Humans↗

PubMed1992

[Clinical characteristics and typological classification of endogenous depression resistant to treatment].

Overall 47 patients suffering from treatment-resistant endogenous depressions were examined. In accordance with psychopathological manifestations, structure and dynamics of the given conditions, typological differentiation was performed. Three main variants, designated as reactive neurotic, endomorphous vital and heteronomic, were described. Differences were shown between resistant and curable endogenous depressions in terms of some clinical, psychopathological and structural signs. A varying character of treatment response under conditions of routine treatment by antidepressants combined with antioxidants is discussed in different clinical varieties of treatment-resistant endogenous depressions.

Adult↗

PubMed2026

Genomic Characterization of ETV6::RUNX1-Positive Childhood B-ALL in a Chinese Cohort: Novel Fusion Partners, Co-Occurring Mutations, and Risk-Stratifying Biomarkers.

BACKGROUND: ETV6::RUNX1 is the most common genetic abnormality in pediatric B-cell acute lymphoblastic leukemia (ALL; ∼25%), yet the comprehensive genetic architecture and molecular predictors of intermediate-risk (IR) stratification remain incompletely characterized. METHODS: We performed whole-transcriptome sequencing (Illumina NovaSeq 6000, rRNA depletion, 41.70 Gb/sample) on bone marrow samples from 93 pediatric ETV6::RUNX1-positive B-ALL patients. Bioinformatics analysis included STAR alignment, MuTect2 variant calling, FusionCatcher fusion detection, and VEP annotation. The Jaccard index with permutation testing assessed mutation co-occurrence; logistic regression identified independent predictors of IR classification. RESULTS: Beyond ETV6::RUNX1, we identified 51 distinct fusion genes across the cohort, including the reciprocal RUNX1-ETV6 (73.1%), chr8::KLF1210 (38.7%), and KLF12-chr8 (34.4%). Somatic mutations in 249 genes were detected; the most frequent were KIAA1715 (17.2%), KRAS (11.8%), and NSD2 (10.8%). Network analysis revealed significant chromatin modifier co-occurrence (KIAA1715-KMT2C: J = 0.136, p = 0.015) and KRAS-NRAS mutual exclusivity (J = 0.000, p = 0.042). PTCH1 (OR = 3.50, 95% CI 0.21-58.49, p = 0.41) and GNB1 (OR = 6.5, 95% CI 1.2-34.8, p = 0.029) mutations independently predicted IR classification. chr8::KLF1210 fusion correlated with higher Day-19 MRD levels (p = 0.038). CONCLUSIONS: GNB1 mutation represents a novel independent predictor of IR stratification in ETV6::RUNX1-positive B-ALL. The chromatin modifier co-occurrence module and extensive fusion architecture reveal biological heterogeneity within this favorable-risk subtype, with potential implications for risk-adapted therapeutic strategies.

B‐ALL↗

PubMed2002

Natural TWIST protein variants in a panel of eleven non-human primates: possible implications of TWIST gene-tree for primate species tree.

The twist gene is implied in head morphogenesis, as human patients heterozygous at TWIST and heterozygous M-twist mutant mice present similar cranial-facial abnormalities. M-twist and TWIST are respectively unique genes, coding for a B-HLH transcription factor. We identified twist coding sequences from 11 species representing 7 families of primates, report their conservation and genus-specific amino acid substitutions, and present a tentative gene-tree of these sequences. Amino acid changes result in natural Twist variants, which might contribute to generating distinct head morphologies in species. These data suggest twist as a molecular marker, which could be used to refine controversial classification.

Amino Acid Sequence↗

PubMed2006

High HPV genetic diversity in women infected with HIV-1 in Brazil.

The present study on genetic diversity of human papillomaviruses in women infected by HIV in Brazil describes the frequency, the genotypes, and five new variants of HPV. One hundred fifty cervical smears of HIV-positive women were subjected to cytological examination, and the DNA samples obtained were assayed by MY09/MY11 amplification, followed by RFLP typing. The overall HPV-DNA-positive rate was 42.7%. One hundred twenty-two samples (81.3%) had benign cellular alterations or normal cytological results, and HPV DNA frequency among them was 30.3%. Otherwise, 96.4% of samples with altered cytology were positive for HPV DNA. A high diversity of genotypes was observed. HPVs-16 and 81 were the most prevalent (14.1%) and were followed by HPVs 52, 35, 62, 33, 53, 56, 66, 70, 18, 58, 6b, 11, 31, 39, 40, 61, 71, 32, 54, 59, 67, 68, 85, and 102. Five new variants of the high-risk HPVs 18, 33, 53, 59, and 66 were detected. Possible associations between the detection of HPV genotypes and the cytological classification, HIV viral load, CD4 count, and antiretroviral treatment were also examined. We observed that a high proportion of HIV-infected women are infected with HPV and may carry oncogenic genotypes, even when cytological evaluation shows normal results.

Adolescent↗

PubMed2000

Age-dependent prevalence of mutations at the GLC1A locus in primary open-angle glaucoma.

PURPOSE: To screen a population with primary open-angle glaucoma for mutations in the gene that encodes the trabecular meshwork inducible glucocorticoid response protein (TIGR), also known as myocilin (MYOC). METHODS: Ophthalmologic information was collected for study subjects with primary open-angle glaucoma and their relatives. Mutation screening of 74 primary open-angle glaucoma probands was conducted by sequencing TIGR/MYOC coding sequence and splice sites. RESULTS: In 23 families we detected 13 nonsynonymous sequence changes, nine of which appear to be mutations likely to cause or contribute to primary open-angle glaucoma. Two mutations, Arg272Gly and Ile499Ser, and one nonsynonymous sequence variant, Asn57Asp, are novel. We found mutations in nine of 25 juvenile glaucoma probands (36%) and two of 49 adult-onset glaucoma probands (4%). Age classification of families rather than individual probands revealed mutations in three of nine families with strictly juvenile primary open-angle glaucoma (33%), and no mutations in 39 families with strictly adult-onset primary open-angle glaucoma (0%). In families with mixed-onset primary open-angle glaucoma containing both juvenile primary open-angle glaucoma and adult-onset primary open-angle glaucoma cases, we found mutations in eight of 26 families (31%). CONCLUSIONS: Our data suggest that Gly252Arg, Arg272Gly, Glu323Lys, Gln368STOP, Pro370Leu, Thr377Met, Val426Phe, Ile477Asn, and Ile499Ser are likely to play roles that cause or contribute to the etiology of autosomal dominant primary open-angle glaucoma. Our finding of more TIGR/MYOC mutations in families with mixed-onset primary open-angle glaucoma than in the families with strictly adult-onset primary open-angle glaucoma implies that the presence of relatives with juvenile primary open-angle glaucoma in a family could be used as a basis for identifying a subset of the population with adult-onset primary open-angle glaucoma with higher prevalence of TIGR/MYOC mutations. To address this issue, and to refine estimations of mutation prevalence in these age-defined subpopulations, prospective study of a larger population ascertained entirely through adult-onset primary open-angle glaucoma probands will be needed.

Adolescent↗

PubMed1999

[Worldwide consensus: the way from the KIEL classification to the REAL classification to the WHO classification].

The history of lymphoma classification has been long and controversial. However, within the last thirty years much has been learned about the biology of lymphoma. The concept of classifying malignant lymphoma according to the (proposed) normal counterpart was developed in the KIEL classification. In 1994, the so-called revised European/American lymphoma classification was published as a consensus of pathologists from both sides of the Atlantic. Its clinical significance was proven in the International Lymphoma Classification Project. The upcoming WHO-Classification is based on the principle to define disease entities that can be recognized by the pathologists and are of clinical relevance. Within these entities, histopathological variants and clinical subtypes are described, which may or may not bear prognostic relevance. Prognostic factors can be defined within an entity, on a clinical, morphological, immunohistochemical or genetic basis.

Diagnosis, Differential↗

PubMedDate not supplied

[Comparative embryology of nematodes and the law of embryo similarity].

Two types of embryonic development can be distinguished within nematodes, with a variable (Enoplia) or invariant (remaining species) cleavage. In the case of invariant cleavage two main variants of cell lineage are presented in nematodes, with the posterior (Rhabditea) or anterior (Dorylaimida) localization of endoderm material at the two-cell stage. This classification is in a good agreement with some modern nematode taxonomy and it is supported by molecular phylogeny studies. The variable cleavage is plesiomorphic. Traditional concept of "mosaic" cleavage is not applicable for nematodes as inductive interactions and a regulation of experimental interventions are usual attributes of any mode of nematode development. The representatives of order Rhabditida have almost identical cell lineage, but at the same time they have strong interspecific differences in mechanisms of ooplasmic segregation any early inductive interactions. The diversity of geometric patterns in the early cleavage, often at the level of individual random variations, is a usual characteristic of nematodes including species with the invariant cleavage. Thus, the early stages of nematode development are evolutionary very flexible, but at the course of embryonic development similarity of different species is progressively increased up to the uniform morphogenetic stages. The dynamics of variation in nematode development contradict to the von Baer's law but are in an agreement with the modern "hourglass model" (Doboul, 1994; Raff, 1986).

Animals↗

PubMedDate not supplied

Typing of field rabies virus strains in FR Yugoslavia by limited sequence analysis and monoclonal antibodies.

A total of 32 rabies virus isolates (15 of fox, 14 of cat and 3 of dog origin) from the territory of FR Yugoslavia were collected from December 1996 till February 1998 and analyzed by limited sequencing of N gene and by indirect immunofluorescence and a panel of 20 antinucleocapsid monoclonal antibodies (MAbs). All examined strains were characterized as sylvatic fox strains. Two main genetic variants were detected, 15 isolates belonging to Group I, 14 belonging to Group II, while the remaining 3 could not be classified into any group. This classification was confirmed by MAbs. The obtained results indicate at least two independent cycles of rabies transmission, probably resulting from multiple modes of transmission to the territories now belonging to FR Yugoslavia.

Animals↗

PubMed1992

Lack of prognostic value of histopathologic parameters in Hodgkin's disease, nodular sclerosis type. A study of 123 patients with limited stage disease who had undergone laparotomy and were treated with radiation therapy.

The value of histopathologic parameters in predicting the long-term overall survival probabilities was studied in a series of 123 patients with pathologic stage IA, IB, IIA, IIB, or IIIA Hodgkin's disease, nodular sclerosis type who were treated with curative radiation therapy. The parameters that were studied included the relative proportion of atypical vs reactive cells, amount of eosinophils, presence of necrosis, degree of mitotic activity, intensity of different types of mesenchymal reactions, classification in three subtypes (ie, lymphocyte predominance, mixed cellularity, and lymphocyte depletion) or in two grades (ie, grades 1 and 2), and identification of the syncytial variant. For each parameter, the association with clinical risk factors was also analyzed. The results of this study show that there are no pathologic features that carry a significant predictive value of the overall survival.

Adolescent↗

PubMed2005

[Role of molecular screening for common fusion genes in the diagnosis and classification of leukemia].

OBJECTIVE: To assess the value of common fusion genes analysis in the diagnosis and classification of leukemia by multiplex RT-PCR. METHODS: The multiplex RT-PCR, including 8 parallel PCR reactions, could screen 86 mRNA breakpoints or splice variants at the same time, which was important for the diagnosis and prognosis of leukemia. Bone marrow samples from 161 cases of leukemia and 8 cases of myelodysplastic syndrome (MDS) were involved in the study. The distribution of common fusion genes in leukemia was analyzed by the method mentioned above in combination with clinical and morphological features. RESULTS: Ten fusion genes were detected in 115 cases of leukemia, including AML1/ETO, PML/RAR alpha, PLZF/RAR alpha, dupMLL, MLL/AF6, MLL/AF10, CBFbeta/MYH11, BCR/ABL, Hox11, and EVI1 BCR/ABL was positive in all the 52 cases of chronic myeloid leukemia; PML/RAR alpha was found in 21 of 25 acute promyelocytic leukemia (APL), and PLZF/RAR alpha was detected in one case of APL. Sixteen cases of 17 AML1/ETO-positive acute leukemia (AL) belonged to FAB-M2 subtype, and one case was mixed leukemia. Three of 4 AL cases carrying CBFbeta/MYH11 were M4 subtype, and one was M5 subtype. MLL aberrations were found in 16 AL, in which all MLL/AF6 translocation existed in M5 subtype with classic monoblastic characters. Furthermore, BCR/ABL was detected in 5 acute lymphoblastic leukemia (ALL) cases. Fusion genes were also found in 2 MDS cases, of which AML1/ETO positive-MDS-RAEB progressed to AML rapidly. CONCLUSION: Screening of common fusion genes by multiplex RT-PCR is an important tool which could provide useful and reliable molecular genetic information for the diagnosis and treatment of leukemia.

Adolescent↗