Genetics analysis with down syndrome and histopathological examination of buccal epithelial cells / Análisis genético y examen histopatológico de las células epiteliales bucales en pacientes con síndrome de down

Down syndrome is primarily caused by trisomy of chromosome 21. We reviewed cytogenetic studies performed on 1048 patients who were referred to the Cytogenetics Unit at Dicle University Hospital, Diyarbakir, Southeast Turkey, between 2000 and 2009. The cases were grouped according to the reason of referral for cytogenetic analysis. The highest frequencies of abnormal karyotypes were found among cases that were referred due to suspicion of Down syndrome (84.8 percent). For histologic examination to persons with Down syndrome and normal, buccal mucosa smear was prepared by rubbing. Down syndrome are disabled and control groups were compared statistically buccal epithelial cells and nuclei (p<0.05). Periphery of the nucleus in some patients with Down's syndrome, while the bud structures in the form of micronuclei was observed in the karyolytic cells.

El síndrome de Down es causado principalmente por la trisomía del cromosoma 21. Se revisaron los estudios citogenéticos realizados en 1.048 pacientes que fueron remitidos a la Unidad de Citogenética del Dicle University Hospital, Diyarbakir, sudeste de Turquía, entre los años 2000 y 2009. Los casos se agruparon de acuerdo a la razón de referencia para el análisis citogenético. Las frecuencias más altas de cariotipos anormales se encontraron ent los casos que fueron remitidos por sospecha de síndrome de Down (84,8 por ciento). Para el estudio histológico de las personas con y sin síndrome de Down, se realizó el frotis de mucosa oral por hisopado. Los grupos con síndrome de Down y de control (sin síndrome) se compararon estadísticamente en relación a las células epiteliales orales y los núcleos (p <0,05). Se observaron núcleos periféricos en algunos pacientes con síndrome de Down, mientras que estructuras de tipo brotes en la forma de micronúcleos se observaron en las células cariolíticas.

Chromosome heteromorphisms are more frequent in couples with recurrent abortions.

Chromosomal heteromorphism is considered a variant of a normal karyotype, but it is more frequent in couples with repeated miscarriages. We investigated chromosomal heteromorphism in couples with repeated miscarriages in comparison with a control group. A total of 455 couples who applied to our genetic diagnosis laboratory in Diyarbakir, Turkey, were evaluated for chromosome heteromorphisms; 221 of these couples (the study group) had recurrent abortions and 234 of them (the control group) had no history of abortions and had at least one living child. The patient group of couples with recurrent abortions were found to have a significantly higher rate of chromosome heteromorphism (8.4%) in comparison with the control group (4.9%). When the patients were evaluated according to gender, males had a significantly higher rate of chromosome heteromorphism (11.3%) than females (5.4%). We conclude that since couples with recurrent abortion and males have higher rate of chromosome heteromorphism, cases of heteromorphism should not be disregarded in the etiological investigation of recurrent abortions. Further research should be done to investigate the phenotypic effects of chromosome heteromorphism.

Role of p53 codon 72 polymorphism in chromosomal aberrations and mitotic index in patients with chronic hepatitis B

Polymorphisms of the p53 gene, which participates in DNA repair, can affect the functioning of the p53 protein. The Arg and Pro variants in p53 codon 72 were shown to have different regulation properties of p53-dependent DNA repair target genes that can affect various levels of cytogenetic aberrations in chronic hepatitis B patients. The present study aimed to examine the frequency of chromosomal aberrations and the mitotic index in patients with chronic hepatitis B and their possible association with p53 gene exon 4 codon 72 Arg72Pro (Ex4+119 G>C; rs1042522) polymorphism. Fifty-eight patients with chronic hepatitis B and 30 healthy individuals were genotyped in terms of the p53 gene codon 72 Arg72Pro polymorphism by PCR-RFLP. A 72-h cell culture was performed on the same individuals and evaluated in terms of chromosomal aberrations and mitotic index. A high frequency of chromosomal aberrations and low mitotic index were detected in the patient group compared to the control group. A higher frequency of chromosomal aberrations was detected in both the patient and the control groups with a homozygous proline genotype (13 patients, 3 control subjects) compared to patients and controls with other genotypes [Arg/Pro (38 patients, 20 control subjects) and Arg/Arg (7 patients, 7 control subjects)]. We observed an increased frequency of cytogenetic aberrations in patients with chronic hepatitis B. In addition, a higher frequency of cytogenetic aberrations was observed in p53 variants having the homozygous proline genotype compared to variants having other genotypes both in patients and healthy individuals.

Role of p53 codon 72 polymorphism in chromosomal aberrations and mitotic index in patients with chronic hepatitis B.

Polymorphisms of the p53 gene, which participates in DNA repair, can affect the functioning of the p53 protein. The Arg and Pro variants in p53 codon 72 were shown to have different regulation properties of p53-dependent DNA repair target genes that can affect various levels of cytogenetic aberrations in chronic hepatitis B patients. The present study aimed to examine the frequency of chromosomal aberrations and the mitotic index in patients with chronic hepatitis B and their possible association with p53 gene exon 4 codon 72 Arg72Pro (Ex4+119 G>C; rs1042522) polymorphism. Fifty-eight patients with chronic hepatitis B and 30 healthy individuals were genotyped in terms of the p53 gene codon 72 Arg72Pro polymorphism by PCR-RFLP. A 72-h cell culture was performed on the same individuals and evaluated in terms of chromosomal aberrations and mitotic index. A high frequency of chromosomal aberrations and low mitotic index were detected in the patient group compared to the control group. A higher frequency of chromosomal aberrations was detected in both the patient and the control groups with a homozygous proline genotype (13 patients, 3 control subjects) compared to patients and controls with other genotypes [Arg/Pro (38 patients, 20 control subjects) and Arg/Arg (7 patients, 7 control subjects)]. We observed an increased frequency of cytogenetic aberrations in patients with chronic hepatitis B. In addition, a higher frequency of cytogenetic aberrations was observed in p53 variants having the homozygous proline genotype compared to variants having other genotypes both in patients and healthy individuals.

The ESHRE PGD Consortium: 10 years of data collection.

BACKGROUND: Since it was established in 1997, the ESHRE PGD Consortium has been collecting data from international preimplantation genetic diagnosis (PGD) centres. Ten papers have been published, including data from January 1997 to December 2007. METHODS: The data collection originally used a hard-copy format, then an excel database and finally a FileMaker Pro database. The indications are divided into five categories: PGD for chromosome abnormalities, sexing for X-linked disease, PGD for single gene defects, preimplantation genetic screening (PGS) and PGD for social sexing. The main end-points are pregnancy outcome and follow-up of deliveries. RESULTS: In data collection I, 16 centres contributed data, which increased to 57 centres by data X (average of 39 centres per data collection). These centres contributed data on over 27 000 cycles that reached oocyte retrieval. Of these cycles, 61% were for aneuploidy screening, 17% for single gene disorders, 16% for chromosomal abnormalities, 4% for sexing of X-linked disease and 2% for social sexing. Cumulatively, 5187 clinical pregnancies gave rise to 4140 deliveries and 5135 newborns (singletons: 3182, twins: 921, triplets: 37). CONCLUSIONS: In this paper, we present an overview of the first 10 years of PGD data, highlighting trends. These include the introduction of laser-assisted biopsy, an increase in polar body and trophectoderm biopsy, new strategies, methodologies and technologies for diagnosis, including recently arrays, and the more frequent use of freezing biopsied embryos. The Consortium data reports represent a valuable resource for information about the practice of PGD.

Evaluation of clinical and cytogenetic findings on 1,068 second-trimester amniocenteses in Southeast Turkey.

OBJECTIVE: To investigate the indications of amniocentesis for the detection of chromosomal abnormalities among a sample of patients in Southeast Turkey. MATERIAL AND METHODS: Between 2004 and 2007, 1,068 second-trimester amniocentesis tests were performed in the Medical Biology and Genetics Department Laboratory at Dicle University. Amniotic fluids were cultured by using long-term tissue culture for prenatal diagnosis with cytogenetic analysis. The clinical and cytogenetic findings on 1,068 second-trimester amniocenteses were analyzed. The indications, the proportions of karyotypes according to indications and complications were summarized. RESULTS: Among the 1,068 amniocentesis cases, the maternal age between 35 and 39 years was the most common age group (34.5%). Of the clinical indications abnormal maternal serum screening results were the most common indication for amniocentesis (37.6%). Of 52 cases (4.9%) with detected chromosomal aberrations, 39 were numeric (27 trisomies, 10 sex chromosome aberrations and two triploidies) and 13 were structural (2 reciprocal translocations, 2 Robertsonian translocations and 6 inversions). The highest detection rate of chromosome aberrations was in cases undergoing amniocentesis for abnormal maternal serum screening combined with abnormal ultrasound (US) findings (8.0%). CONCLUSION: This study suggests that complementary measures, such as routine antenatal US and maternal serum screening, should be added to increase the efficiency of genetic amniocentesis. Therefore, the study could be used for the establishment of a database for genetic counseling.

A small supernumerary marker chromosome, derived from chromosome 22, possibly associated with repeated spontaneous abortions.

We report a phenotypically normal couple with repeated spontaneous abortions and without other clinical features. Clinical, hematological, biochemical, and endocrinological aspects of the couple did not reveal any abnormalities. The karyotype of the wife was normal (46,XX), while the husband was found to have an abnormal karyotype, 47,XY,+der(22)mat. The marker chromosome was familial and non-satellite. Although the potential risk of small supernumerary marker chromosomes for spontaneous abortions cannot be defined precisely, marker chromosomes, together with methods used for ascertainment, are also factors to be considered when investigating infertility consequences. Furthermore, identification of the origin of a marker chromosome may provide additional information for patient karyotype-phenotype correlations. Further studies, such as molecular analyses to identify the breakpoint, are necessary for investigating phenotype-genotype correlations and assessment of genetic risks for small secondary chromosomes. The cause of repeated spontaneous abortions in this couple might be the presence of this marker chromosome in the husband. Consequently, we recommended genetic counseling before further pregnancies.

Cytogenetic analysis of 4216 patients referred for suspected chromosomal abnormalities in Southeast Turkey.

We reviewed cytogenetic studies performed on 4216 patients who were referred to the Cytogenetics Unit at Dicle University Hospital, Diyarbair, Southeast Turkey, between 2000 and 2009. The cases were grouped according to the reason of referral for cytogenetic analysis. The frequencies of the different types of numerical and structural abnormalities were determined, and the relative frequency of cases with abnormal karyotypes was calculated in each group. The most common reason for requesting cytogenetic testing was referral for Down syndrome and for repeated abortions. The highest frequencies of abnormal karyotypes were found among cases that were referred due to suspicion of Down syndrome (84.8%). Among the chromosomal abnormalities, sexual chromosomal abnormalities were found in 239 cases (17.6%), and Klinefelter syndrome was the most frequent sex chromosomal abnormality. Autosomal abnormalities were found in 1119 cases (82.4%), and Down syndrome was the most frequent autosomal chromosomal abnormality. In conclusion, the high rate of chromosomal abnormalities (32.2%) found in this population demonstrates the importance of cytogenetic evaluation in patients who show clinical abnormalities. This is the first report on cytogenetic testing in the southeast region of Turkey. This type of study provides a basis for determining the risks of recurrence and for deciding on clinical treatment and genetic counseling.

CYP17 genetic polymorphism in patients with endometrial hyperplasia and cancer.

We investigated the association of CYP17 gene polymorphism with the risk of having endometrial cancer and a well-known precursor of it, endometrial hyperplasia. Group A (control group) consisted of 35 patients who had histologically proven normal endometrium. Group B and C consisted of 18 and 30 patients who had endometrial hyperplasia with and without atypia, respectively. Group D consisted of 57 patients who had endometrial cancer. Venous blood samples were collected from patients in groups, and polymerase chain reaction was performed to determine the CYP17 gene polymorphism. Significant increase of A1/A1 and a decrease of A1/A2 genotype frequencies have been determined in patients with endometrial cancer and with atypical endometrial hyperplasia. No significant differences were found between groups in the frequency of A2/A2 genotype. There was no significant difference between the groups in the meaning of allele distributions. CYP17 polymorphism had correlation with endometrial atypia and cancer. Related effects of different types of CYP17 gene variants on the progression of hyperplastic endometrial cells into carcinoma should be evaluated in further studies. Progress in this area would help us modulate preventive treatments used in those actual high-risk group patients.

Activated Protein C Resistance in Polycythemia Vera.

Activated protein C resistance is a result of a point mutation in factor V gene (Leiden mutation) and can be identified in approximately 50% of patients with thrombosis, making it an important risk factor for thrombosis. The aim of this study is to evaluate the role activated protein C resistance in the hypercoagulable state seen in polycythemia vera. We compared patients with polycythemia vera (n: 24) for increased risk of thromboembolism and activated protein C resistance, with the results of patients with chronic myelogenous leukemia (n: 27) and healthy control group (n: 52). Activated protein C resistance test and factor VIII activity was determined by an aPTT based test. Anticardiolipin antibodies IgG and IgM were also determined by ELISA. Leiden mutation was studied with polymerase chain reaction. Venous thromboses were observed in 12.5% and arterial thromboses in 41.6% of patients with polycythemia vera. Arterial thromboses were recognized in 7.4% of patients with chronic myelogenous leukemia. Activated protein C resistance was identified in 20.8% of patients with polycythemia vera and 14.8% with chronic myelogenous leukemia (versus 1.8% of healthy control subjects). The risk of thrombosis in patients with polycythemia vera was independent from the presence of activated protein C resistance. Leiden mutation was observed in only 1 patient out of 4 patients with chronic myelogenous leukemia who had activated protein C resistance, but not thrombosis. Factor VIII levels of patients with chronic myelogenous leukemia (158% ± 14) were higher than healthy control subjects (99% ± 15) (p< 0.05). Patients with activated protein C resistance in both groups had no seropositivity for anticardiolipin antibodies IgG and IgM. Activated protein C resistance and in some cases its association with Leiden mutation in polycythemia vera may not have a major role in the pathogenesis of thromboembolic complications of polycythemia vera.

Assessment of the value of fibronectin as a tumour marker in malignant pleural mesothelioma.

Fibronectin concentrations both in plasma and pleural effusion were prospectively determined in 60 patients with exudative pleural effusions. Fibronectin concentrations in plasma and pleural fluid in 12 patients with infectious and exudative pleural effusions (mean +/- SD) were 240 +/- 103 and 212 +/- 115 micrograms.mL-1, in 17 patients with primary or metastatic lung carcinoma 242 +/- 104 and 210 +/- 82 micrograms.mL-1, in 13 patients with pleural tuberculosis 246 +/- 77 and 231 +/- 133 micrograms.mL-1, and in 18 patients with confirmed malignant pleural mesothelioma 261 +/- 119 and 276 +/- 188 micrograms.mL-1. There were no significant differences either in the plasma or serum concentrations of fibronectin between groups (p > 0.05). Although pleural fluid fibronectin content appeared to have high specificity (85%), it was found to be an inefficient biological marker for differentiating nonmalignant from malignant pleural effusions due to its low sensitivity (6%).

Variable expression of CD49d antigen in B cell chronic lymphocytic leukemia is related to disease stages.

We have investigated the expression of the dual specific adhesion molecule, VLA-4 (CD49d/CD29) on lymphocytes obtained from 62 patients with B-CLL and compared it with normal controls, patients with other hematological malignancies, and umbilical cord blood. The mean CD49d expression in patients with CLL was lower than the other group of leukemia and the CD19+, CD5+ cells of normal peripheral blood and umbilical cord blood (P < 0.001). The patients in RAI stage 0, I and II (early stage) had even lower CD49d expression, whereas patients in RAI stage III and IV (advanced stage) had relatively higher CD49d levels. In vitro adhesion of lymphocytes to fibronectin, being the extracellular matrix ligand of CD49d, was also investigated. Lymphocytes obtained from B-CLL were found to have lower adhesion to fibronectin than that from controls (P < 0.03). Furthermore, CD49d(low) B-CLL cells had lower adhesion to fibronectin, whereas CD49d(high) B-CLL cells showed normal adhesion ratios (P < 0.002). Further phenotypic analyses revealed the presence of myeloid markers (CD13 and CD33) in most of the advanced stage patients, although these were negative in early stage cases. Expressions of CD11a and sIgM were also low but CD11b was relatively higher in the early stages of the disease. On the basis of these results, we concluded that early stages of CLL are correlated with the expression of CD49d(low), CD11a(low), CD11b(high), CD13-, CD33-, sIgM(low) and also had lower fibronectin adhesion, whereas advanced stages of CLL are associated with CD49d(high), CD11a(high), CD11b(low), CD13+, CD33+, SIgM(high) and show normal fibronectin adhesion.