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Öğe Chromosome heteromorphisms are more frequent in couples with recurrent abortions(Funpec-Editora, 2012) Akbas, H.; Isi, H.; Oral, D.; Turkyilmaz, A.; Kalkanli-Tas, S.; Simsek, S.; Balkan, M.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.Öğe Cytogenetic analysis of 4216 patients referred for suspected chromosomal abnormalities in Southeast Turkey(Funpec-Editora, 2010) Balkan, M.; Akbas, H.; Isi, H.; Oral, D.; Turkyilmaz, A.; Kalkanli, S.; Simsek, S.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.Öğe Cytogenetic and clinical study of a male infant with ambiguous genitalia(Springer, 2007) Oral, D.; Balkan, M.; Duran, H.; Oen, A.; Alp, M. N.; Budak, T.[Abstract Not Available]Öğe Cytogenetic and Y chromosome microdeletion screening studies in infertile males with Oligozoospermia and Azoospermia in Southeast Turkey(Springer/Plenum Publishers, 2008) Balkan, M.; Tekes, S.; Gedik, A.In view of the genetic risks for the next generation, the importance of careful evaluation of karyotypes and AZF microdeletions in male infertility prior to assisted reproduction is evident. In the present study, it is aimed to investigate the frequency and types of both major chromosomal abnormalities by using standard cytogenetic methods and Y chromosome microdeletions of infertile males with azoospermia and oligozoospermia to give appropriate genetic counseling before assisted reproduction techniques in southeast Turkey. A total of 80 infertile males (52 were azoospermic, 25 oligospermic and 3 asthenospermic) were studied for the cytogenetic evaluation and molecular AZF screening program prior to use of assisted reproduction techniques. A detailed history was taken for each man. Karyotyping was performed on peripheral blood lymphocytes according to standard methods. Polymerase chain reaction (PCR) amplification by using 15 Y-specific sequence-tagged sites of AZF region was performed to screen the microdeletions in the AZF region of Y chromosome. Of 80 cases, 71 had normal karyotype (46,XY). The total prevalence of chromosomal abnormalities was found to be 11.2% (9/80), including seven patients with Klinefelter syndromes and two patients with balanced autosomal rearrangements. All of the patients with Klinefelter Syndrome had azoospermia, but carriers with translocation had oligospermia. The deletions of Y chromosome were seen in one patient (1.3%) with features of normal karyotype and azoospermia. Microdeletions were seen in the AZFc and AZFd regions. Neither AZFa nor AZFb microdeletions were detected. The occurrence of chromosomal anomalies and Y chromosome microdeletions among infertile males strongly suggests the need for routine genetic testing and counseling prior to employment of assisted reproduction techniques.Öğe Evaluation of clinical and cytogenetic findings on 1,068 second-trimester amniocenteses in Southeast Turkey(7847050 Canada Inc, 2011) Balkan, M.; Akbas, H.; Kalkanli, S.; Sakar, M. N.; Fidanboy, M.; Alp, M. N.; Budak, T.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.Öğe Genetics Analysis with Down Syndrome and Histopathological Examination of Buccal Epithelial Cells(Soc Chilena Anatomia, 2013) Kalkanli, S.; Simsek, S.; Balkan, M.; Akbas, H.; Isi, H.; Oral, D.; Turkyilmaz, A.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%). 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.Öğe MicroRNA-related gene polymorphisms and idiopathic azoospermia(Wiley-Blackwell, 2016) Balkan, M.; Ay, O. I.; Erdal, M. E.; Rustemoglu, A.; Atar, M.; Hatipoglu, N. K.; Yildiz, I.[Abstract Not Available]Öğe No association between catalase (CAT) gene polymorphisms and susceptibility to vitiligo in a Turkish population(Soc Editrice Univ, 2013) Akbas, H.; Dertlioglu, S. B.; Dilmec, F.; Balkan, M.Background and Aims. Vitiligo is an acquired hypomelanotic skin disorder resulting from the loss of functional melanocytes from the cutaneous epidermis. Low catalase (CAT) activity and Accumulation of hydrogen peroxide (H2O2) have been demonstrated in the epidermis of vitiligo patients. Some polymorphisms on catalase gene may have effect on the quantity and activity of catalase enzyme. The aim of this study was to investigate whether catalase (CAT) gene polymorphisms are associated with susceptibility to vitiligo in Turkish population. Materials and Methods. One hundred and three patients with vitiligo and one hundred and seven gender, age and ethnic matched controls were enrolled in the study. Genotyping was done by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results. The CAT gene -89A>T (rs7943316) and 389C>T (rs769217) genotypes and allele frequencies of vitiligo patients did not differ significantly from those of healthy controls. Conclusions. We found no association between CAT gene -89A>T and 389C>T polymorphism and vitiligo susceptibility in Turkish vitiligo patients. Further studies with greater sample size should be performed to verify these results.Öğe Recessive Complex Brachydactyly, Symphalangism, Zygodactyly and Male Infertility - not a Novel Syndrome but Caused by Linked Mutations in BMPR1B and PDHA2, a New Male Infertility Gene(Nature Publishing Group, 2018) Yildirim, Y.; Ouriachi, T.; Woehlbier, U.; Ouahioune, W.; Balkan, M.; Malik, S.; Tolun, A.[Abstract Not Available]Öğe A small supernumerary marker chromosome, derived from chromosome 22, possibly associated with repeated spontaneous abortions(Funpec-Editora, 2010) Balkan, M.; Isi, H.; Gedik, A.; Erdemoglu, M.; Budak, T.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.
