The role of gene encoding collagen secretion protein (SERPINH1) in the pathogenesis of a hypermobile type of Ehlers-Danlos syndrome.

Introduction: Hypermobile (hEDS) Ehlers-Danlos syndrome (EDS) is a non-inflammatory, autosomal dominant connective tissue disorder. hEDS, unlike other types of EDS, has no known genetic aetiology, so diagnosis is conducted based on a person's medical history, a physical examination, and exclusion of other types of EDS after genetic tests. Aim: The present study was a sequencing analysis of the SERPINH1 gene and the evaluation of the potential impact of variants of this gene on their role in the aetiology of the hypermobile type of EDS. Material and methods: The study group included 100 hEDS patients of Polish origin. The SERPINH1 gene analysis was performed on genomic DNA (gDNA). In all patients, other types of EDS or other connective tissue disorders were excluded by testing them with NGS technology. Results: Among 100 tested patients, 4 different types of missense variants (heterozygote) were detected. All SERPINH1 alterations were classified as benign according to ACMG guidelines. Conclusions: Mutations in the SERPINH1 gene have been described in a rare type of OI but have never been analysed in hypermobile Ehlers-Danlos syndrome. In our investigation among 100 hEDS patients, we did not identify pathogenic or likely pathogenic variants. Though only benign variants were detected, which play no role in the pathogenesis of hEDS, we should take into account mechanisms other than gene structure alterations, which may have an impact on collagen and other ECM protein transport.

Next-Generation Sequencing of Connective Tissue Genes in Patients with Classical Ehlers-Danlos Syndrome.

BACKGROUND: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. MATERIAL AND METHODS: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. RESULTS: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. DISCUSSION: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet.

The impact of oophorectomy on survival from breast cancer in patients with CHEK2 mutations.

BACKGROUND: To estimate the impact of oophorectomy and other treatments on the survival of breast cancer patients with a CHEK2 mutation. METHODS: Women with Stage I-III breast cancer who were treated at 17 hospitals in Poland were tested for four founder mutations in the CHEK2 gene. 974 women (10%) were positive for a CHEK2 mutation. Control patients without a CHEK2 mutation were selected from a database of patients treated over the same time period. Information on treatments received and distant recurrences were retrieved from medical records. Treatments included chemotherapy, hormonal therapy (tamoxifen) and radiation therapy. Oophorectomies were performed for the treatment of breast cancer or for benign conditions. Dates of death were obtained from the Polish Vital Statistics Registry. Causes of death were determined by medical record review. Predictors of survival were determined using the Cox proportional hazards model. RESULTS: In all, 839 patients with a CHEK2 mutation were matched to 839 patients without a mutation. The mean follow-up was 12.0 years. The 15-year survival for CHEK2 carriers was 76.6% and the 15-year survival for non-carrier control patients was 78.8% (adjusted HR = 1.06; 95% CI: 0.84-1.34; P = 0.61). Among CHEK2 carriers, the 15-year survival for women who had an oophorectomy was 86.3% and for women who did not have an oophorectomy was 72.1% (adjusted HR = 0.59; 95% CI: 0.38-0.90; P = 0.02). Among controls, the 15-year survival for patients who had an oophorectomy was 84.5% and for women who did not have an oophorectomy was 77.6% (adjusted HR = 1.03; 95% CI: 0.66-1.61; P = 0.90). CONCLUSION: Among women with breast cancer and a CHEK2 mutation, oophorectomy is associated with a reduced risk of death from breast cancer.

Clinical Significance of Gene Mutations and Polymorphic Variants and their Association with Prostate Cancer Risk in Polish Men.

Objectives: We tested the association of germline variants in BRCA1, BRCA2, CHEK2, CDKN2A, CYP1B1, HOXB13, MLH1, NBS1, NOD2 andPALB2 genes, as well as in 8q24 region, with prostate cancer (PC) risk and estimated their impact on disease clinical course, including overall survival time in Polish men with localized PC qualified for radical treatment.Materials and Methods: DNA of 110 patients with localized prostate cancer treated with radical prostatectomy (RP), from each age group and with different stages of the disease. DNA samples of the control group consisted of 111 men, volunteers, without PC (age-matched to study group). Sanger sequencing, AS-PCR, RFLP-PCR, and multiplex-PCR were used for  variants detection.Results: The percentage of men with ≥1 germline variant was higher in PC group (52.7%) than in healthy men (37.8%) (P = .03). The presence of ≥2 variants was associated with shorter survival than the presence of one or no variant in the PC group (P = .14, trend). The HOXB13 G84E was detected in 2.9% of PC men and in no healthy men (P = .19, trend, OR = 7.21). A CHEK2 truncating mutation (1100delC or IVS2+1G>A) was detected in 2/110 (1.8%) PC patients and in no healthy men (P = .29, OR=5.14). The NBS1 I171V was detected in 2/110 (1.8%) PC patients and in no men from the control group (OR=5.14, P = .29, NS).Conclusions: We conclude that the presence of more than 2 germline variants was probably associated with shorter survival of patients with localized prostate cancer qualified for radical treatment. The HOXB13 (G84E), CHEK2 (1100delC or IVS2+1G>A) truncating variants and NBS1 (I171V) are associated with PC and hereditary form of the disease. The HOXB13 (G84E) and NOD2 (3020insC) single variants are associated with shorter and CYP1B1 (48CC, 119GG) single genotypes with longer overall survival.

Gitelman syndrome with normocalciuria - a case report.

BACKGROUND: Gitelman Syndrome (GS) is a hereditary tubulopathy associated with a biallelic inactivating mutations of the SLC12A3 gene encoding the thiazide-sensitive sodium-chloride cotransporter (NCCT). The typical clinical manifestation is a hypokalemic metabolic alkalosis with significant hypomagnesemia, and low urinary calcium excretion. Hypocalciuria is widely believed to be a hallmark of GS that distinguishes it from Barter's syndrome, presenting as hypercalciuria. The pathomechanism of hypocalciuria in GS is not fully elucidated. Up to date, a clinical course of GS with normocalciuria has been reported only in men, while women have a milder course of the disease with typical hypocalciuria, which is believed as the result of sex hormone. Additionally, there is a growing evidence that calcium channels of the distal nephron could be regulated by a variety of hormones, including aldosterone (Aldo). CASE PRESENTATION: We present the case of a 28-year-old Caucasian woman with asymptomatic, chronic hypokalemia, hypomagnesemia, hypochloremic alkalosis and normal urinary calcium excretion. A high renin levels with normal concentration of Aldo in serum have also been found. The values of blood pressure were low. Based on genetic studies, two heterozygous mutations in the trans position were confirmed: c.2186G>T (p.Gly729Val) and c.1247G>C (p.Cys416Ser) in the SLC12A3 gene, which ultimately confirmed the diagnosis of GS. CONCLUSIONS: We report here the first case of genetically confirmed GS manifested as normocalciuria in a Caucasian woman. Thus, our result does not confirm a role of sex hormones on the level of calciuria. Based on the results of normal Aldo concentration despite high renin level in our patient, we hypothesized that Aldo may be connecting with the level of urinary calcium excretion in patients with the GS.

Germline mutations among Polish patients with acute myeloid leukemia.

BACKGROUND: A small but important proportion of patients (4-10 %) with AML have germline mutations. They can cause the development of AML at an earlier age, confer a higher risk of relapse or predispose to secondary leukemias, including therapy-related leukemias. The analysis of germline mutations in a patient and his/her family is also critical for the selection of suitable family donors if the patient is a candidate for hematopoietic stem cell transplantation (HSCT). METHODS: 103 unrelated consecutive patients with de novo AML were enrolled in the study. Control group consisted of 103 persons from the general population. We performed NGS sequencing of bone marrow cells and buccal swabs DNA of six genes: CEBPA, DDX41, ETV6, TERT, GATA2, and IDH2 to detect germline pathogenic mutations. RESULTS: In the investigated group, 49 variants were detected in six genes. 26 of them were somatic and 23 germline. Germline variants were detected in all six tested genes. Eight pathogenic germline mutations were detected in 7 AML patients, in three genes: CEBPA, ETV6, and IDH2. One patient had two pathogenic germinal mutations, one in ETV6 and one in CEBPA gene. We identified one novel pathogenic germline mutation in CEBPA gene. The difference in frequency of all pathogenic germline mutations between the tested (7.77 %) and control groups (0.97 %) was statistically significant (p = 0.046). In the tested group, the median age at AML diagnosis was 11 years lower in patients with pathogenic germline mutations than in patients without them (p = 0.028). CONCLUSIONS: We showed higher frequency of CEBPA, ETV6, and IDH2 germline mutations in AML patients than in control group, which confirms the role of these mutations in the development of AML. We also showed that the median age at the onset of AML in patients with pathogenic germline mutations is significantly lower than in patients without them.

Killer-cell immunoglobulin-like receptor genotype and haplotype combinations in children treated for acute lymphoblastic leukemia.

INTRODUCTION: Acute lymphoblastic leukemia (ALL) is the most common malignancy diagnosed in children. The factors predisposing to ALL remain mostly unknown. Natural killer (NK) cells are a component of innate immunity. Their role is to eliminate cells that were infected with viruses or underwent a neoplastic transformation. The activity of NK cells is regulated by their activating and inhibitory receptors, inter alia killer-cell immunoglobulin-like receptors (KIRs). The available data about a link between the incidence of ALL and KIR genotype are highly inconclusive, and further research is needed to explain whether such a relationship truly exists. The aim of this study was to analyze KIR genotype and haplotype combinations in children treated for ALL. MATERIAL AND METHODS: The study included 49 children diagnosed with ALL at 1.2-19.8 years of age. The control group was composed of 43 healthy subjects aged between 1.2 and 21.9 years. DNA was isolated using QIAamp DNA Mini kits. KIR genotypes were identified by a polymerase chain reaction (PCR) with sequence-specific primers (SSPs). The analysis also included KIR haplotype combinations: AA, AB and BB. RESULTS: Patients with ALL and controls did not differ significantly in the frequencies of individual KIR genes and haplotypes. However, the overall frequency of all 6 activating KIR genes in patients with ALL was significantly higher than in the controls (24.5% vs. 4.7%, p = 0.019). CONCLUSIONS: The findings presented here imply that individual KIR genes do not play a significant role in the pathogenesis of ALL. Nevertheless, a higher number of activating KIR genes may constitute a risk factor for this malignancy.

G84E germline mutation in HOXB13 gene is associated with increased prostate cancer risk in Polish men.

We tested the association between HOXB13 G84E (rs138213197) germline mutation and PC risk in Polish men. DNA from 103 consecutive, newly diagnosed patients hospitalised because of PC and DNA from 103 men: volunteers, healthy at the time of the study. The G84E mutation was genotyped using Sanger sequencing. The HOXB13 G84E germline mutation was detected in 2.9% of PC men (3/103) and not detected in any healthy man. Two mutation carriers originated from two of 25 families fulfilling hereditary prostate cancer criteria (HPC) and one mutation carrier from one family among 78 families without HPC (PC frequency: 8% vs. 1.3%, OR = 6.70, p = 0.13). In two of three mutation carriers, disease was detected above 60 years of age. There was a trend for a lower probability of 5-year survival in patients with G84E than in patients without it (66.7% vs. 94.0%, p = 0.08). The HOXB13 G84E germline mutation is associated with increased prostate cancer risk in Polish men, with hereditary form of the disease, and probably with older age at PC onset (> 60 years of age) and shorter survival. However, it is not associated with PSA level, or PC stage or grade at the time of diagnosis.

New variants in COL5A1 gene among Polish patients with Ehlers-Danlos syndrome: analysis of nine cases.

INTRODUCTION: The Ehlers-Danlos syndrome (EDS) is a non-inflammatory, heritable connective tissue disorder divided into 13 types according to the 2017 International Classification of the Ehlers-Danlos syndromes. One of the subtypes of EDS, classical (cEDS), is characterized by joint hypermobility, skin hyperextensibility and atrophic scars, which are major criteria of cEDS. AIM: In this study, the first in Central Eastern Europe, 44 patients were investigated. All of them were tested for COL5A1 mutations with direct DNA sequencing. MATERIAL AND METHODS: The study group included 44 patients of Polish origin, all of whom fulfilled criteria for the classical type of Ehlers-Danlos syndrome. Direct sequencing of the COL5A1, COL5A2 and COL1A1 c.934C>T genes was performed for all of them. Evaluation of potential pathogenicity of detected missense mutation was conducted using SIFT (Sorting Intolerant from Tolerant), PolyPhen-2, AlignGVGD (Align Grantham Variance/Grantham Difference). The effect of the splice site mutations was predicted by Human Splicing Finder and NetGene2 tools. RESULTS: Among all tested patients, nine mutations of COL5A1 gene were detected (8 missense mutations and 1 splice site). The alterations identified by us are new, hitherto not described in other reports. Evaluation of the mutations by in silico tools indicate their pathogenicity. CONCLUSIONS: Our study is the first COL5A1 gene molecular investigation conducted among cEDS patients from Central Eastern Europe. Besides new COL5A1 variant findings, we gained molecular confirmation of clinical diagnosis of cEDS. In some cases, specific and adequate evaluation and classification of EDS patients based only on clinical features, may be difficult.

Searching for new breast cancer-associated genes. ABRAXAS1 gene mutations in the group of BRCA1-negative patients.

In the present study, we analysed the association of mutations of a BRCA1-associated gene, ABRAXAS1, with the risk of development of breast cancer (BC) in BRCA1-negative women from North-Central Poland. A hundred women with consecutively diagnosed BC and 100 women belonging to the control group were screened for new mutations predisposing to breast cancer. The first step was a test carried out in order to find one of the three Polish founder mutations in the BRCA1 gene. In 96 BRCA1-negative patients two missense variants: c.422C>T and c.1042G>A as well as two intronic variants: IVS3-34G>A, IVS3-44T>C were detected in the ABRAXAS1 gene. The c.422C>T mutation was detected in one of 96 women diagnosed with breast cancer (1.04%); it was not associated with increased risk of disease in this group, compared to the controls (p = 0.49), but the odds ratio was 3.314; 95% CI: 0.122-75.352. IVS3-44T>C was found more frequently in the control group (15/93) than in the tested group (1/85), OR 0.062; 95% CI: 0.008-0.480, p = 0.007, which may suggest protective properties of this variant against tumorigenicity. The data obtained from the present study suggest the necessity for further research to be conducted on the ABRAXAS1 gene in relation to hereditary predisposition to breast cancer.

MRP1 protein expression in leukemic stem cells as a negative prognostic marker in acute myeloid leukemia patients.

BACKGROUND: It is well established that expression of multi-drug resistance (MDR) proteins (MDR1, BCRP, MDR3, MRP1, and LRP) in leukemic blasts correlates with acute myeloid leukemia (AML) patients' clinical response. Assuming that leukemic stem cells (LSC) are resistant to chemotherapy and responsible for relapse, it might be clinically relevant to evaluate the expression level of MDR proteins in LSC and relate it to the clinical outcome. METHODS: Bone marrow samples from 26 patients with de novo AML were labeled with antibodies to distinguish CD34+CD38-CD123+ LSC population and with antibodies against MDR1, BCRP, MDR3, MRP1, or LRP proteins. Multicolor flow cytometry was applied to evaluate the expression of MDR proteins in blasts and LSC. RESULTS: Nine of 26 patients with AML attained CR (30%). High negative correlation was found between MDR1 and LRP expression in blasts and the patient's remission. MDR proteins were expressed more frequently in LSC than in leukemic blasts. High negative correlation was also observed between remission achievement and MRP1 expression in LSC. CONCLUSIONS: Our data present for the very first time the high negative correlation between MRP1 protein expression in LSC and AML patients' remission. It does strongly suggest that MRP1 expression in LSC is an adverse prognostic marker in patients with de novo AML.

Heterogeneity of human WT1 gene.

The WT1 gene, characterized by an extremely complex structure, is located on chromosome 11. It is involved in cell growth and differentiation, and has a strong impact on consecutive stages of the functioning of the body. The WT1 gene may undergo many different mutations, as well as may be overexpressed without a mutation. The molecular basis of diseases such as Wilms tumor, WAGR, Denys-Drash or Frasier syndromes are congenital WT1 mutations, while somatic mutations of this gene occur in acute and chronic myeloid leukemia, myelodysplastic syndrome and also in some other blood neoplasms, as acute lymphoblood leukemia. Increased expression of this gene without its mutation is observed in leukemias and solid tumors. The WT1 may function both as a tumor suppressor gene and as an oncogene. The diversity of WT1 changes causes many controversies, therefore investigations are still carried out to determine the function of this gene, its interaction with other molecules and its prognostic significance in various diseases.

Genetical background of intelligence.

Intelligence as an ability to reason, think abstractly and adapt effectively to the environment is a subject of research in the field of psychology, neurobiology, and in the last twenty years genetics as well. Genetical testing of twins carried out from XX century indicated heritebility of intelligence, therefore confirmed an influence of genetic factor on cognitive processes. Studies on genetic background of intelligence focus on dopaminergic (DRD2, DRD4, COMT, SLC6A3, DAT1, CCKAR) and adrenergic system (ADRB2, CHRM2) genes as well as, neutrofins (BDNF) and oxidative stress genes (LTF, PRNP). Positive effect of investigated gene polymorphism was indicated by variation c.957C>T DRD2 gene (if in polymorphic site is thymine), polymorphism c.472G>A COMT gene (presence of adenine) and also gene ADRB2 c.46A->G (guanine), CHRM2 (thymine in place c.1890A>T) and BDNF (guanine in place c.472G>A) Obtained results indicate that intelligence is a feature dependent not only on genetic but also an environmental factor.

CEBPA copy number variations in normal karyotype acute myeloid leukemia: Possible role of breakpoint-associated microhomology and chromatin status in CEBPA mutagenesis.

Copy number variations (CNV) in CEBPA locus represent heterogeneous group of mutations accompanying acute myeloid leukemia (AML). The aim of this study was to characterize different CEBPA mutation categories in regard to biological data like age, cytology, CD7, and molecular markers, and identify possible factors affecting their etiology. We report here the incidence of 12.6% of CEBPA mutants in the population of 262 normal karyotype AML (NK-AML) patients. We confirmed that double mutant AMLs presented uniform biological features when compared to single CEBPA mutations and accompanied mostly younger patients. We hypothesized that pathogenesis of distinct CEBPA mutation categories might be influenced by different factors. The detailed sequence analysis revealed frequent breakpoint-associated microhomologies of 2 to 12bp. The analysis of distribution of microhomology motifs along CEBPA gene showed that longer stretches of microhomology at the mutational junctions were relatively rare by chance which suggests their functional role in the CEBPA mutagenesis. Additionally, accurate quantification of CEBPA transcript levels showed that double CEBPA mutations correlated with high-level CEBPA expression, whereas single N-terminal CEBPA mutations were associated with low-level CEBPA expression. This might suggest that high-level CEBPA expression and/or accessibility of CEBPA locus contribute to B-ZIP in-frame duplications.

CD117 (c-kit) expression on CD34+ cells participates in the cytogenetic response to imatinib in patients with chronic myeloid leukemia in the first chronic phase.

BACKGROUND: Chronic myeloid leukemia (CML) biology seemed to be perfectly explored especially at the beginning of the tyrosine kinase inhibitors era. Later years with imatinib and second-generation tyrosine kinase inhibitors showed a variety of resistance mechanisms and it became obvious that the bcr-abl chimeric gene is not the only enemy to fight. Some studies assumed the decreased rate of programmed cell death (apoptotic) to be the primary mechanism by which BCR-ABL affects expansion of the leukemic clone in CML. Therefore, the aim of this study was to investigate the role of c-kit inhibition in treatment response. METHODS: Cytogenetic analysis, real-time quantitative reverse-transcriptase polymerase chain reaction, flow-cytometric analysis and imatinib serum level quantification were applied. RESULTS: The percentage of CD34+ cells expressing c-kit (CD117) isolated from bone marrow samples of 54 CML patients treated with standard-dose imatinib was significantly lower among imatinib responders. The fraction of apoptotic CD34+CD117+ cells in this patient group was significantly higher than in nonresponders. CONCLUSION: To achieve optimal treatment response in CML patients, the elimination of CD34+CD117+ may be necessary through an apoptotic pathway.

A risk of breast cancer in women - carriers of constitutional CHEK2 gene mutations, originating from the North - Central Poland.

BACKGROUND: Germline mutations of the CHEK2 gene have been reported to be associated with breast cancer. In this study, we analyzed the association of CHEK2 mutations with the risk of development of breast cancer in women of North-Central Poland. METHODS: 420 women with breast cancer and 435 controls were tested for three protein truncating (IVS2 + 1G > A, 1100delC, del5395) and one missense (I157T) CHEK2 mutation. IVS2 + 1G > A and I157T mutations were identified by RFLP-PCR, 1100delC variant was analyzed using an ASO-PCR and del5395 mutation by multiplex-PCR. The statistical tests: the odds ratio (OR) and Fisher's exact test were used. RESULTS: In 33 out of 420 (7.9%) women consecutively diagnosed with breast cancer, we detected one of four analyzed CHEK2 mutations: I157T, 1100delC, IVS2 + 1G > A or del5395. Together they were not associated with the increased risk of breast cancer (North-Central control group: OR = 1.6, p = 0.124; the general Polish population: OR = 1.4, p = 0.109). This association was only seen for IVS2 + 1G > A mutation (OR = 3.0; p = 0.039). One of the three truncating CHEK2 mutations (IVS2 + 1G > A, 1100delC, del5395) was present in 9 of 420 women diagnosed with breast cancer (2.1%) and in 4 of 121 women (3.3%) with a history of breast cancer in a first- and/or second- degree relatives. Together they were associated with the increased risk of disease in these groups, compared to the general Polish population (OR = 2.1, p = 0.053 and OR = 3.2; p = 0.044, respectively). I157T mutation was detected in 25 of 420 women diagnosed with breast cancer (6.0%) and in 8 of 121 women (6.6%) with a history of breast cancer in first- and/or second- degree relatives. The prevalance of I157T mutation was 4.1% (18/435) in North-Central control group and 4.8% (265/5.496) in the general Polish population. However it was not associated with an increased risk of breast cancer. CONCLUSION: Obtained results suggest that CHEK2 mutations could potentially contribute to the susceptibility to breast cancer. The germline mutations of CHEK2, especially the truncating ones confer low-penetrance breast cancer predisposition that contribute significantly to familial clustering of breast cancer at the population level.

[Hereditary prostate cancer]. / Dziedziczny rak gruczolu krokowego.

Prostate cancer (PC) is one of the most common cancers affecting men. It may soon become the main cancer--caused mortality among men all over the world. The genetic basis of prostate cancer is very complex and its etiology is poorly understood. The genes associated with hereditary predisposition to prostate cancer remain largely unknown. Family history of PC, particularly at a young age, is a strong risk factor. Through linkage analysis, numerous prostate cancer susceptibility chromosomal loci have been identified, including: HPC1 (1q24-25), PCaP (1q42.2-43), HPCX (Xq27-28), CAPB (1p36), HPC2 (17p12), HPC20 (20q13). However, it turned out that any of these genes is not a high-risk prostate cancer susceptibility gene. According to literature data HPC is associated with genes involved in androgen metabolism, including androgen receptor gene--AR, SRD5A2 and CYP17, genes involved in the DNA damage repair, including BRCA1, BRCA2, NBS1 and MLH1 or some developmental genes as HOXB13. Identification of PC high predisposition susceptibility genes is very important, because the ascertainment of a higher risk of prostate cancer development in mutation carriers enable to develop and implement in clinical practice suitable prophylactic programs which could prevent the disease or detect it in an early stage. It seems that better knowledge of the molecular pathology of prostate cancer could make it easier to discover new drugs of chemopreventive and chemotherapeutic activity. There are many cellular pathways associated with PC cancerogenesis, which may become a potential goal for such drugs in the future.

[The hematological malignancies related to primary hypereosinophilia and their diagnostics]. / Nowotwory ukladu krwiotwórczego przebiegajace z pierwotna hipereozynofilia i ich diagnostyka.

Published in 2008, by experts of the World Health Organization, the new classification of hematological malignancies forced a change of look at chromosomal aberrations and gene mutations, which are important in establishing the diagnosis and prognosis for patients with these malignancies. The new classification includes a new category of neoplasms - hematological malignancies with hypereosinophilia. Due to the high diversity of causes of hypereosinophilia and underlying genetic changes, their differential diagnosis is based on classical cytogenetics, fluorescence in situ hybridization (FISH) and genetic molecular techniques. Cytogenetic analysis of bone marrow cells showed that the majority of hypereosinophilia cases can be characterized by the presence of normal karyotype. Therefore, routine cytogenetic diagnostics should be complemented by FISH with break-apart probes for potentially rearranged genes (e.g., CBFB, ETV6) and unique probes for fusion genes (e.g., FIP1L1-PDGFRA), specific for hypereosinophilia-associated diseases. In differential diagnosis of hypereosinophilia, the analysis of characteristic gene mutations (e.g., cKIT) and gene fusions (e.g., ETV6-PDGFRB) is also applied, using molecular genetic methods.