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Approximately, 13-18% of couples who want to have children suffer from infertility problems. Of these problems nearly 20% can be attributed solely to male factors. The production of functionally competent and genetically normal spermatozoa is strictly controlled by genetic regulations and a variety of impairments to this system are associated with a higher aneuploidy rate, poor sperm parameters as well as low or zero sperm counts, which are the main reasons for male infertility. Today, modern infertility treatments, such as ICSI help patients to overcome severe male infertility and to conceive. However, it is important to consider that such treatments also provide a route for transmitting hereditary genetic disorders to the next generation. Therefore, couples should be counselled about the risks and in their ART cycles preimplantation genetic diagnosis (PGD) can be carried out to eliminate the risk of sperm dependent chromosomal abnormalities and other paternally inherited disorders in the developing embryos. Genetic factors identified so far, such as microdeletions in the Y chromosome, numerical and structural chromosomal aberrations, mutations in the cystic fibrosis transmembrane conductance regulator gene and de-novo mutations as well as androgen receptor mutations have been linked to male factor infertility. During the last 5 years, more than 2000 couples have been referred for genetic counselling to our ART clinic for several reasons. A total of 1214 patients with non-obstructive azoospermia (NOA) and 721 patients with severe oligoasthenoteratozoospermia (SOAT) were genetically screened via karyotyping and Y-microdeletion analysis before initiation of their ART treatments. The overall incidence of cytogenetic abnormalities and Y microdeletions among them was 12.5% and 7.7%, respectively. Additionally, sperm FISH analyses were applied to cases with structural chromosomal abnormalities, including translocations and inversions, and to cases having poor embryo development, implantation failures, and early miscarriages in their previous ART cycles to detect the potential effects of sperm aneuploidy on embryogenesis. Moreover, PGD was applied to 549 male infertility cases of which 445 were for chromosomal screening and 104 were for chromosomal rearrangements. Today, it is well documented that there are identifiable genetic reasons for male infertility. Therefore, genetic screening and counselling have great importance for these patients. Additionally, the authors' results showed a high frequency of chromosomal abnormality in karyotype and Y-microdeletion analyses in men with poor quality semen parameters, thus genetic results should be reported before initiation of their IVF cycles to decide treatment approaches. Regarding the correlation of embryo aneuploidy and poor sperm parameters, the pregnancy rate in the PGD applied male infertility group was found to be higher than that in the group that had not received PGD. Consequently, genetic screening and PGD should be considered as a choice of treatment for cases suffering from male factor infertility. [ABSTRACT FROM AUTHOR]

Introduction: Preimplantation genetic diagnosis (PGD) is an essential alternative to prenatal diagnosis for couples at risk of having an affected child because of single gene disorder. When prenatal diagnosis was made, if the result were an affected fetus, termination of pregnancy would be requested. So, it could cause ethical problems and high stress for the couples. Selection of unaffected embryos generated by IVF is only way to avoid these problems. This study consists of PGD applications for 29 different single gene disorders and their molecular tools. Materials/Methods: A total of 84 couples (111 cycles) came to our genetic centre for PGD of single gene diseases between 2002 and 2007. in all, 1603 oocytes were collected, 1255 of those were fertilized and 887 embryos were selected for biopsy. Nested PCR was used as a molecular technique. Multiplex PCR was performed in first step on the blastomeres biopsied from day-3 embryos. Desired regions were amplified in a second step. According to mutation of single gene, minisequencing method, fragment analysis or linkage analysis were used to determine mutations or mutation-containing alleles. Results: A total of 753 (85%) embryos were diagnosed for 29 different single gene diseases (beta-thalassaemia, cystic fibrosis, Neiman pick, fragile X, CMT, SMA, NF, FMF, etc.). There were 249 (33%) embryos transferred after diagnosis and 53 (49%) biochemical pregnancies were obtained in 107 transfer cycles. There were 40 healthy babies born from 27 (50%) births; 14 pregnancies are continuing. Conclusion: Because of the advantages of PGD over prenatal diagnosis, number of couples and types of single gene disorders are increasing in our centre. The results show the success of PGD applications for several single gene disorders using nested PCR. [ABSTRACT FROM AUTHOR]

Introduction: Preimplantation genetic diagnosis is an alternative to prenatal diagnosis for people who are carriers for spinal muscular atrophy (SMA). Spinal muscular atrophy is a severe neurogenerative autosomal recessive disorder. 90-95% of SMA patients have homozygous deletion in exon 7 of the SMA gene. The aim of this study was to report on the application of PGD for SMA from 2003 to 2007. Materials/Methods: PGD was performed for l0 couples who are SMA carriers. In total, 83 blastomeres were biopsied for diagnosis of SMA. Two-step (nested PCR) was used as a molecular technique. Multiplex and single-plex PCR were performed respectively on the blastomeres biopsied from day 3 embryos. Exon 7 and its dependent polymorphic single tandem repeat (STR) markers were amplified and, using minisequencing reactions, absence or presence of deletion in exon 7 was determined. Polymorphic STR markers were also used to confirm the mutation by linkage analysis. Results: In all, 71 blastomeres were diagnosed for SMA and 23 of them were transferred; l0 embryo transfer cycles were performed in I l cycles. One of these was cancelled because of the absence of a healthy blastomere. Ten cycles resulted in five pregnancies and six healthy babies were born. Conclusion: PGD is an opportunity for SMA-carrier couples for having a healthy child. According to our results, using minisequencing and STR markers together for SMA in PGD is a reliable method. [ABSTRACT FROM AUTHOR]

Objective: Male infertility is present in up to half of infertile cases. This could be a result of genetic factors, such as numerical and structural chromosomal abnormalities and microdeletions of the Y chromosome. Cytogenetic and molecular screening analysis give valuable guidance in assisted reproduction treatments. Materials/Methods: From March 2000 to September 2007, 1935 infertile men, 1214 with non-obstructive azoospermia (NOA) and 721 with oligoasthenoteratozoospermia (OAT), were referred to our ART and Reproductive Genetics Centre. World Health Organization 1999 criteria were taken into consideration for the evaluation of semen parameters and Kruger strict criteria was applied for the evaluation of sperm morphology. Karyotype analysis of 1935 cases was done using conventional cytogenetic techniques. For Y-deletion screening, genomic DNA was extracted from peripheral blood using a commercial kit. Twenty-five loci in the Yq region were amplified by multiplex polymerase chain reaction (PCR) with homemade primers. Results: The overall incidence of cytogenetic abnormalities was 12.45%. Klinefelter syndrome was the most frequent cytogenetic abnormality (10.95%) found in NOA group and both reciprocal and Robertsonian translocations (1.80% and 1.66%) are found to be the most frequent abnormalities in OAT group. The overall incidence of Y-chromosome microdeletion (n = 105) was 7.7%. The deletion rates were 1.85% and 9.5% for OAT and NOA groups, respectively. A total of 34 patients with microdeletions initiated treatment. Ejaculate sperm could be obtained from four patients with partial AZFc deletions. Micro-testicular sperm extraction (TESE) was applied to 30 patients with partial deletions of AZFa/b/c regions and spermatozoa were retrieved in 14 cases (46%). TESE was cancelled for 50 cases with complete AZFa and AZFb deletions. Conclusion: According to this study, the incidence of having either a cytogenetic abnormality or microdeletion in Y chromosome was 16.6%. High frequency of abnormality suggests the need for genetic screening and counselling. The results of karyotype and Y-microdeletion analysis should be in hand before initiation of assisted reproduction cycles to give patient proper treatment. Preimplantation genetic diagnosis (PGD) is an option for most of male infertility cases and should be offered with insistence to patients with structural rearrangements and numerical mosaicisms. Intracytoplasmic sperm injection together with testicular sperm aspiration, TESE, micro-TESE and PGD applications made and is continuing to make dreams come true for these particular patients. [ABSTRACT FROM AUTHOR]

Introduction: Beta-thalassemia is an autosomal recessive haematopoietic single gene disorder. Human leukocyte antigen (HLA) identical donor is the unique way to cure haematopoietic disorders like beta-thalassaemia. Therefore, HLA typing in PGD applications is an important technique to prevent couples having an affected child. The objective of this study is to report our PGD beta-thalassaemia HLA cases between 2002 and 2007. Materials/Methods: A total of 103 couples were studied for beta-thalassaemia with HLA typing. 175 cycles were performed for these couples. Nested PCR was used to amplify both beta-thalassaemia and HLA regions. Beta-thalassaemia mutations were determined both minisequencing and single tandem repeat (STR)-linked markers. HLA compatibility was determined by STR linkage markers. Results: Totally 1738 blastomeres were analysed; 1410 were diagnosed for beta-thalassaemia and 1568 of them were diagnosed for HLA matching; 187 embryos have been transferred in 117 cycles; 47 biochemical pregnancies have occurred; 16 live births have occurred on time and the 15 cases are still pregnant. Conclusion: PGD is a great hope for familial carriers of beta-thalassaemia and have an ill child. We report that techniques used to diagnose beta-thalassaemia and HLA-matching cases are quite reliable. Using these reliable techniques for this great purpose is one of the most important aim of our hospital. [ABSTRACT FROM AUTHOR]

Objective: Chromosomal rearrangements are one of the major causes of recurrent spontaneous abortions and repeated IVF failures. Translocation carriers are a subgroup who derive benefit from preimplantation genetic diagnosis (PGD). Here we .present our results of PGD cycles for translocation carriers and discuss the factors related with the success of outcome. Materials/Methods: Between 2000 and 2008, 126 couples underwent 174 PGD cycles. A total of 83 patients were carrying reciprocal translocation (RecT), 42 patients were carrying Robertsonian translocation (RobT) and one patient was carrying both RecT and RobT. One cell was removed from each embryo on day 3 via laser biopsy. Blastomeres were fixed with hypotonic solution 3:1 fixative method. Commercially supplied telomeric, locus-specific and centromeric fluorescence in-situ hybridization (FISH) probes were used; for cases with advanced maternal age (AMA), at least chromosomes 13 and 21 were included in the study. Sperm FISH analysis was applied to 15 male translocation carriers. Results: A total of 117 cycles for RecT carriers and 57 cycles for RobT carriers resulted in 27% and 30% pregnancies respectively. For RecT carriers 22% and RobT carriers, 36% of embryos were found to be normal or balanced. When patients were grouped with respect to the age of woman, for RecT carriers, women whose age were lower than 37 years have a clinical pregnancy rate (CPR) of 33% while this rate dramatically decreases to 9% for older women. This same age effect was slightly observed in RobT group since the CPR of young (30.5%) and old (25%) patients did not differ much. Miscarriage rate was 9%. Embryonic parameters are affected according to the gender of the carrier; slow-growing embryos on day 3 and/or 4 are more prevalent in female carriers. The sperm FISH study revealed that average unbalanced spermatozoa in RecT carriers was 77.1% and in RobT carriers 22.5%, while abnormal embryo rates were 78% and 64% in RecT and RobT carriers, respectively. Conclusion: Factors such as limited ovarian reserve and AMA had negative impact on outcomes of RecT carriers, due to low chance of replacing a normal or balanced embryo. With a history full of miscarriages, these patients benefit from PGD, which reduced miscarriage rates while giving acceptable rates of pregnancy. In addition, strong correlation was found between sperm FISH results and abnormal embryo rates for RecT carriers while the same correlation could not be found for RobT carriers. Furthermore, a gender effect was observed on embryonic developmental parameters. Besides the factors mentioned above, type of rearrangement, positions of breakpoints and interchromosomal effects are another important factors affecting the success. [ABSTRACT FROM AUTHOR]

Objective: Chromosomal abnormalities in embryos are thought to be responsible for repeated implantation failures (RIF). Here we discuss possible beneficial effects of preimplantation genetic diagnosis (PGD) in couples with three or more failed IVF attempts with maternal ages below 37 years. Materials/Methods: Between years 2000 and 2008, 225 patients underwent 259 PGD cycles for RIF. Mean number of trials and duration of infertility were 4.3 and 9.4, respectively. One cell was removed from each embryo on day 3 via laser biopsy. Hypotonic solution/3:1 fixative method was used for fixation of nuclei. Commercially supplied 5-chromosome (13, 16, 18, 21,22), 9-chromosome (13, 15, 16, 17, 18,21,22, X, Y) and 12-chromosome (8, 13, 14, 15, 16, 17, 18, 20, 21,22, X, Y) probe panels were used in hybridization studies. Sperm fluorescence in-situ hybridization (SF) test was applied to 20 male partners. Furthermore, pregnancy rates (PR) were compared according to use of culture medium, endometrial co-culture versus commercial culture, in the last year. Results: Out of 1766, 951 (54%) embryos were diagnosed as abnormal. Complex aneuploidy and haploidy/polyploidy were observed in half of (48%) abnormal embryos. In eight cycles, embryo transfer was cancelled due to absence of normal embryos. Clinical pregnancy was achieved in 103 patients (41%). 13 pregnancies were ended due to ectopic pregnancy (n = 3), anembryonic pregnancy (n = 2) and missed abortion (n = 8). 65 pregnancies resulted in birth of 79 healthy babies. A total of 25 pregnancies are still continuing. A slight but not significant increase in aneuploidy rate was found in SF analysis. PR was higher in endometrial co-culture group (63%) compared with the commercial culture group (50%). Conclusion: Genetic factors alone or together with clinical factors and immunological factors might be responsible for RIF. Even though, no correlations were observed in SF studies, it does not exclude paternal effects. High rates of complex abnormalities in embryos suggest problems related to both oocyte and spermatozoa in post-meiotic machinery such as expression of cell cycle checkpoint genes, disorganization of microtubules, centrosome defects, etc. The results of this study shows that PGD, together with co-culture, is an effective treatment option for couples with RIF. [ABSTRACT FROM AUTHOR]

Objective: PGD for aneuploidy is a valuable and effective tool in increasing assisted reproduction outcome and decreasing the abortion in poor prognosis patients. The purpose of this study was to evaluate clinical impact of PGD through the analysis of the reproductive outcome before and after PGD in the same group of poor prognosis IVF patients, undergoing PGD for chromosomal abnormalities. Materials/Methods: The implantation rate (IR) and spontaneous abortion rate after PGD was retrospectively compared with reproductive history of same patients. Based on a series of 792 PGD cycles from 2000 to 2006 in Memorial Hospital IVF and Genetic Centre for numerical chromosomal abnormalities, resulting in the establishment of 226 chromosomal abnormality-free clinical pregnancies, the previous history of 139 patients, whose historical data were available, were analysed. A total of 333 cycles in 139 patients (for who, previous obstetric history was available) included 168 PGD cycles and 165 non-PGD cycles. Chi-squared test was used for the statistical analysis. Results: A total of 476 embryo transfers were performed in 165 non-PGD cycles and a total of 48 sacs were observed: IR: 48/476, 10.08%; mean maternal age: 29.9 ± 9.19 years. 337 embryo transfers were performed in 168 PGD cycles and a total of 192 sacs were observed: IR: 192/337, 56.6%; mean maternal age: 33 ± 11.31 years (P < 0.001). The abortion rate for both assisted reproduction pregnancies and spontaneous pregnancies of non-PGD cycles were compared with 139 PGD patients: non-PGD abortion rate: 89/173, 51.4%. PGD applied group: 337 embryos transferred, 192 sacs implanted (56.6% IR per PGD cycle). A total of 151 babies delivered in 120 pregnancies, 17 sacs aborted in 15 pregnancies, 16 sacs ongoing in 11 pregnancies, six fetal reduction and two ectopic pregnancies excluded from study: abortion rate: 15/146, 10.2% (exception of reductions and ectopic pregnancies) (P < 0.001). Take-home baby rate in 226 chromosomal abnormality free clinical pregnancies was 151/226 (66.8%) per pregnancy. Conclusion: The results demonstrate a strong clinical impact of PGD, resulting in reduction of spontaneous abortion, improvement of implantation rate and increase in the take-home baby rate in poor prognosis infertile couples. [ABSTRACT FROM AUTHOR]