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The invasive procedures amniocentesis and chorionic villus sampling (CVS) are routinely applied in pregnancies at risk for fetal abnormalities and the results obtained are the gold standard for prenatal diagnosis. Because these methods of fetal cell procurement involve a 0.5-2% risk for fetal loss, they are recommended mainly in cases at high risk for fetal genetic or cytogenetic abnormalities. The development of a reproducible, reliable, noninvasive method based on retrieval of rare fetal cells from the maternal circulation will render testing feasible for the general population. Despite intensive investigation, a satisfactory, clinically acceptable method has not yet emerged. Several cell types have been targeted to this end, mostly nucleated red blood cells (NRBC), CD34+ hematopoietic progenitors, and trophoblasts. Although these cell types have been unequivocally proven to be present in the maternal circulation, each bears a significant disadvantage, rendering their application in clinical testing currently impossible: NRBC cannot be expanded in culture, thereby ruling out metaphase chromosome analysis, an essential component of prenatal diagnosis. CD34+ cells do posses the potential for in vitro proliferation, however, they have been found to persist in the maternal circulation after delivery, thereby complicating diagnosis in consecutive pregnancies. Trophoblasts are not consistently detected in the maternal circulation. Moreover, due to the lack of a definitive fetal cell marker and a reliable sorting method, foolproof fetal cell identification of any of these cell types is not possible. This report outlines the obstacles that impede development of a method for noninvasive fetal cell sampling for prenatal genetic diagnosis, along with a description of our efforts to analyze simultaneously two fetal blood cell types, NRBC and CD34+ cells in maternal blood during pregnancy, and the problems encountered. This work and that of others lead us to suggest potential future directions to help develop this important technique.

Objective Our purpose was to get an overview of the genetic events leading to the development of familial and sporadic ovarian tumors and to identify chromosomal regions that may contain genes important in tumor progression. Methods The comparative genomic hybridization (CGH) technique was employed in a total of 46 epithelial ovarian or peritoneal tumors: 27 sporadic tumors, 11 tumors disected from BRCA1 mutation (185delAG) carriers, and eight from BRCA2 mutation (6174delT) carriers (familial tumors). Results The average number of genetic alterations (deletions and amplifications) was significantly (α=0.0069) higher in familial tumors (9.17 ± 4.25 alterations per tumor in the BRCA1 mutation carriers and 7.25 ± 6.06 in the BRCA2 mutation carriers) compared to the sporadic group (4.26 ± 3.61 alterations per tumor). The pattern of the chromosome amplifications resembled in the three groups and the most common amplifications detected were at chromosomes 8q, 3q, and 2q. The pattern of the chromosomal deletions varied between the groups. Among the BRCA1 group, the most common deletions were in chromosomes 9 and 19. The BRCA2 group showed a lower frequency of deletions. Deletion of chromosome 16 and 22 were the most frequent ones. No specific chromosomal deletion was significantly indicated in the sporadic group. Conclusions Familial ovarian tumors exhibit a significantly higher number of chromosomal aberrations and genomic imbalances and nonrandom genetic changes were characterized in the BRCA1 and BRCA2 groups.

Abnormal recombination between the X and Y chromosomes during meiosis, occurring outside the pseudoautosomal region, can result in translocation of the SRY gene from the Y to the X chromosome, and consequently in abnormal sexual differentiation, such as the development of 46,XX males or true hermaphroditism. In this report we present clinical, cytogenetic, and molecular-cytogenetic data of a patient with ambiguous genitalia and true hermaphroditism, who had a unique mosaic karyotype, comprising three different cell lines: 46,XX(SRY+), 45,X(SRY+), and 45,X. The mosaic karyotype of our patient probably represents two different events: abnormal recombination between the X and Y chromosomes during paternal meiosis, and postzygotic loss of one of the X chromosomes. Replication studies demonstrated that in 80% of the XX cells, the SRY sequence was located on the active X chromosome. This finding suggests nonrandom X inactivation and, together with the presence of the SRY gene, explains the male phenotype of our patient. On the other hand, the presence of the 45,X cell line may have contributed to genital ambiguity. We conclude that fluorescence in situ hybridization (FISH) analysis with SRY probes is highly recommended and allows accurate diagnosis and optimal management in cases of 46,XX hermaphroditism and ambiguous genitalia.

Ionizing irradiation to the skull is a known risk factor for meningioma development. To gain insight into the molecular mechanisms that underlie radiation-associated meningioma (RAM), we characterized the somatic genetic alterations in 16 RAMs by using comparative genomic hybridization and compared the pattern of alterations with 17 nonradiation-associated meningiomas (non-RAM). Most tumors (29/33;87.9%) displayed at least one DNA copy number alteration, and 11 out of 33 (33%) exhibited four or more changes. The mean number of DNA copy number changes was similar in RAMs (2.4+/-1.9) and in non-RAMs (2.5+/-1.9). The most common DNA losses were noted in chromosome 22 (56.2% in RAM, and 47% in non-RAM) and chromosome 1 (37.5% in RAM and 35.3% in non-RAM), with no significant differences between the two groups. Noteworthy, gain in DNA copy number of chromosomes 8 and 12 was detected in two RAM tumors only. In conclusion, no significant differences were noted between RAMs and non-RAMs regarding the number of genetic changes and the extent and frequency of chromosomes 1 and 22 losses. These preliminary data suggest that the tumorogenic pathways of meningioma formation are similar, regardless of previous skull irradiation.

To investigate the potential paternal contribution to the risk of fetal chromosomal anomalies after intracytoplasmic sperm injection (ICSI).Spermatozoa isolated from testicular tissue and ejaculated specimens of consenting patients undergoing testicular biopsy and ICSI were analyzed for chromosomes X, Y, and 18 by FISH.Assisted reproductive technology program.Consenting patients undergoing testicular biopsy and ICSI, severe oligozoospermic patients, and normal fertile donors.None.The rate of chromosome abnormalities in testicular sperm with regard to the type of azoospermia and ejaculated sperm compared to healthy men.The mean serum levels of FSH in the groups with nonobstructive azoospermia (n = 9), obstructive azoospermia (n = 10), severe oligozoospermia (n = 9), and the normal donors (n = 6) were 17.5 +/- 8.2 (P.05), 3.5 +/- 2.6, 14.6 +/- 3.5 (P.05), and 3.1 +/- 0.4 IU/mL, respectively. The corresponding rates of sperm chromosome abnormalities among these groups were 19.6% (P.001), 8.2% (P.001), 13.0% (P.001), and 1.6%, respectively. The corresponding rates of disomy among these groups were 7.8% (12 of 153 spermatozoa), 4.9% (18 of 367), 6.2% (109 of 1,751), and 1% (5 of 500 spermatozoa), respectively. Errors in chromosomes X and Y were significantly more common than in chromosome 18.The present findings demonstrate a linkage between gonadal failure (high serum FSH levels) and the occurrence of sperm chromosome aneuploidies. Our findings may explain the increased incidence of sex chromosome abnormalities found after IVF in the severe male factor patient population. Genetic screening during pregnancy or before embryo replacement should be considered carefully.

The clinical spectrum of caudal dysplasia sequence (CDS) is noted for its diversity. The origin of CDS remains unknown, though poorly controlled gestational diabetes has been implicated in some cases. Here we describe the case of a newborn with CDS associated with penile enlargement (PE). The main anomalies included anal atresia, agenesis of the kidneys and of the sacrococcygeal vertebrae, dysgenesis of lumbar vertebrae, and bilateral cryptorchidism. Penile enlargement (7 cm), a rather unusual finding, has so far not been reported in association with CDS. Chromosomal analysis failed, and the neonate died 30 min after birth. Comparative genomic hybridization analysis using stored DNA showed a balanced normal male DNA content, which negates chromosomal losses or gains as a cause of CDS and/or PE. PE due to virilizing-type adrenal hyperplasia, caused by common mutations in the genes encoding for the adrenal enzymes 21-hydroxylase and 11-hydroxylase, was ruled out. We report on a previously unpublished case of the coexistence of PE and severe CDS and propose a possible pathogenetic hypothesis of this association.

Objective: The aim of the study was to determine the potential risk for fetal chromosomal anomalies in non-mosaic Klinefelter's syndrome patients undergoing IVF and intracytoplasmic sperm injection. Design: Individually collected spermatozoa were isolated from wet testicular tissue preparations and fixed on glass slides using micromanipulation. Their nuclei were analyzed for chromosomes X, Y, and 18 by fluorescent in situ hybridization. Setting: Assisted reproductive technology program. Patient(s): Consenting patients with non-mosaic Klinefelter's syndrome undergoing testicular biopsy and IVF (fresh specimens) or following such treatment (cryopreserved specimens). Intervention(s): None. Main Outcome Measure(s): The rates of numerical chromosome abnormalities for chromosomes X, Y, and 18 among spare testicular sperm and the pregnancy outcome following treatment. Result(s): Testicular sperm were found in 8 of 20 patients. Four couples became pregnant following embryo replacement. Sperm chromosomes were analyzed in five patients. One hundred and five sperm of 112 analyzed (93.7%) were normal with X to Y ratio of 50:55 (NS) respectively. Among the 112 sperm tested, seven (6.3%) demonstrated chromosomal abnormalities, of which five were related to the sex chromosomes and two to chromosome 18. One set of triplets, one set of twins, and two singletons (four males and three females) with normal karyotypes were born. Conclusion(s): Most of the testicular sperm retrieved from Klinefelter's syndrome patients demonstrates a normal pattern of sex chromosome segregation. Therefore, the risk of transmitting numerical sex chromosome abnormalities is relatively low and probably comparable with the rates found in other severe male factor infertility patient groups.

Primary central nervous system neoplasms are the most common solid tumors in children. Genetic changes underlying childhood brain-tumor development and progression are incompletely characterized. To get an overview of the genetic events leading to the development of brain tumors and to identify chromosomal regions that may contain genes important in brain-tumor progression, we employed a comparative genomic hybridization technique. Twenty-four pediatric primary brain tumors were analyzed in this study. DNA copy number changes were observed in most of the samples (79%), and almost all chromosomes were involved. The total number of genetic aberrations (copy-number gains and losses per tumor) was significantly higher in the cerebellar primitive neuroectodermal tumor subgroup than in the gliomas. The high-grade tumors had more DNA changes than did the low-grade tumors. The most often gained chromosomes were: 6q (45%), 4q (34.5%), and chromosome 1 (24% of the cases). The minimal common regions involved in DNA gains were narrowed down to 6q14-16 and 4q26-28. Losses of a specific chromosome (partly or as a whole) occurred on average in 7% of the cases. Chromosomal regions that were most often lost included chromosome 1 (17%), chromosome 16 (17%), and chromosome 2 (14%). These findings suggest that genes localized to these minimal common chromosomal regions play a role in the tumorogenesis of childhood brain tumors. Our results indicate: (1) a great degree of genomic imbalance in these tumors; (2) that a high number of aberrations correlate with aggressive tumor biology; (3) and that nonrandom genetic changes may be associated with particular tumor types.

We report on three cases of partial trisomy 2p in which the identification and exact localization of the duplicated chromosome segment was possible only by application of molecular cytogenetic techniques. These included fluorescence in situ hybridization by use of wcp2, N-myc, and subtelomeric 2p probes and comparative genomic hybridization with DNA isolated from blood samples, frozen fetal tendon, and formalin fixed, paraffin-embedded fetal lung tissue. Two of the cases concerned fetuses of gestational week 20 and 24 with duplication of nonoverlapping terminal (2pter-->p24) and more proximal (2p25-->p23) segments and with distinctly different phenotypes. The third case was due to a de novo inverted duplication of 2p25-->p23, with loss of the subtelomeric region of 2p. This 53-month-old girl was a Bloom syndrome carrier. The patient had prenatal growth failure, borderline microcephaly, dilated lateral horns of the cerebral ventricles, transient cortical blindness, myopia, muscle hypotonia, and dilatation of the left renal collecting system. Dermal cysts were found on the glabella, the soles of both feet, and the vocal cord, causing respiratory embarrassment. Previously reported cases of pure trisomy 2p are reviewed, in an attempt to correlate clinical findings to overlapping regions in 2p. These cases illustrate the effectiveness of molecular cytogenetic methods in resolving subtle chromosomal aberrations in order to coordinate more accurately a chromosome regionspecific phenotype.

In order to investigate the dynamics of genomic alterations that occur at different developmental stages in vitro, we examined the chromosome content of human preimplantation embryos by molecular-cytogenetic techniques at the single-cell level, up to 13 days post fertilization.The embryos were genetically analyzed several times during their development in culture; each embryo was first analyzed by FISH at 'Day 3' post fertilization, than during its growth in vitro and the third analysis was performed at development arrest, then the entire blastocyst was analyzed by comparative genomic hybridization (CGH/aCGH).We found that while on 'Day 3' only 31% of the embryos were detected as normal, on 'Day 5-6', 44% of the embryos were classified as normal and on 'Day 7', 57% were normal. On 'Days 8-13', 52% of the embryos were classified as chromosomally normal. One third of the embryos that were chromosomally abnormal on 'Day 3', were found to be normal at development arrest point.These dynamic changes that occur at early developmental stages suggest that testing a single blastomere at 'Day 3' post fertilization for PGD might inaccurately reflect the embryo ploidy and increase the risk of false aneuploidy diagnosis. Alternatively, blastocyst stage diagnosis may be more appropriate.

Eight infertile men with various degrees of oligoasthenoteratozoospermia and repeated implantation failure were selected for this study due to exceptionally high rates of sperm aneupoidy in their ejaculates. All subjects had normal physical examination, karyotype and serum FSH concentration. Prior to IVF treatment, spermatozoa was collected, processed, micromanipulated and tested for chromosomes X, Y and 18 using fluorescence in-situ hybridization. Aneupoidy rates for chromosomes X, Y and 18 were determined among sperm population selected for normal morphology using high-order magnification light microscopy. A second group of fast motile spermatozoa were collected using an intracytoplasmic sperm injection pipette from the medium–oil interface from microdroplets. The average aneuploidy rates for the three chromosomes were 7.6% (395/5182) in the sperm specimen before selection, 8.7% (116/1326) in the normal morphology selected group and 4.3% (59/1388; P P Eight infertile men with various degrees of oligoasthenoteratozoospermia and repeated implantation failure were selected for the study due to exceptionally high rates of sperm aneupoidy in their ejaculates. All subjects had normal physical examination, karyotype and serum FSH concentration. Prior to IVF treatment, spermatozoa was collected, processed, micromanipulated and tested for chromosomes X, Y and 18 using fluorescence in-situ hybridization. Aneupoidy rates for chromosomes X, Y and 18 were determined among sperm population selected for normal morphology using high-order magnification light microscopy. A second group of fast motile spermatozoa were collected using an ICSI pipette from the medium–oil interface from microdroplets. The average aneuploidy rates for the three chromosomes were 7.6% (395/5182) in the sperm specimen before selection, 8.7% (116/1326) in the normal morphology selected group and 4.3% (59/1388, P

Pluripotency and proliferative capacity of human embryonic stem cells (hESCs) make them a promising source for basic and applied research as well as in therapeutic medicine. The introduction of human induced pluripotent cells (hiPSCs) holds great promise for patient-tailored regenerative medicine therapies. However, for hESCs and hiPSCs to be applied for therapeutic purposes, long-term genomic stability in culture must be maintained. Until recently, G-banding analysis was considered as the default approach for detecting chromosomal abnormalities in stem cells. Our goal in this study was to apply fluorescence in-situ hybridization (FISH) and comparative genomic hybridization (CGH) for the screening of pluripotent stem cells, which will enable us identifying chromosomal abnormalities in stem cells genome with a better resolution. We studied three hESC lines and two hiPSC lines over long-term culture. Aneuploidy rates were evaluated at different passages, using FISH probes (12,13,16,17,18,21,X,Y). Genomic integrity was shown to be maintained at early passages of hESCs and hiPSCs but, at late passages, we observed low rates mosaiciam in hESCs, which implies a direct correlation between number of passages and increased aneuploidy rate. In addition, CGH analysis revealed a recurrent genomic instability, involving the gain of chromosome 1q. This finding was detected in two unrelated cell lines of different origin and implies that gains of chromosome 1q may endow a clonal advantage in culture. These findings, which could only partially be detected by conventional cytogenetic methods, emphasize the importance of using molecular cytogenetic methods for tracking genomic instability in stem cells.

Congenital diaphragmatic hernia (CDH) is a relatively common malformation of unknown cause with high mortality due to hypoplasia of the lungs and pulmonary hypertension. We studied a family in which two fetuses had CDH, and two pregnancies resulted in first trimester missed abortions. Both fetuses with CDH had an apparently normal karyotype. In a subsequent pregnancy, fluorescent in situ hybridization analysis of amniocytes showed a balanced translocation 46,XY, t(5;15) (p15.3;q24) also present in the mother and in a normal child, suggesting that the diaphragmatic hernia in the first two fetuses was caused by a cryptic unbalanced translocation. This hypothesis is supported by a previous observation of CDH in a distal deletion of 15q as part of a multiple congenital anomalies syndrome. It is suggested that a gene distal to 15q21 is important for the normal development of the diaphragm.

To report the performance of fluorescence in-situ hybridization in the setting of preimplantation genetic diagnosis in order to diagnose embryos affected by DiGeorge syndrome.Case report.Academic referral center.A 32 year-old female affected by DiGeorge syndrome.History and physical examination, karyotyping, amniocentesis, preimplantation genetic diagnosis, fluorescence in-situ hybridization.Avoidance of pregnancy with embryo affected by DiGeorge syndrome.Termination of pregnancy with an affected embryo followed by fluorescence in-situ hybridization based preimplantation genetic diagnosis and delivery of healthy offspring.The combination of preimplantation genetic diagnosis with fluorescence in-situ hybridization is recommended to prevent pregnancies with DiGeorge syndrome affected embryos in properly selected patients.

To assess the putative correlation between comparative genomic hybridization (CGH)-detectable genetic alterations in epithelial ovarian cancer and disease recurrence, conventional CGH was performed on 45 epithelial ovarian cancers: 26 tumors from sporadic, BRCA mutation noncarriers and 11 and 8 tumors from BRCA1 and BRCA2 mutation carriers, respectively. Relevant clinical data, including histology, grade, stage, size of residual tumor, recurrence, and survival, were obtained from outpatient and inpatient charts. Among the 45 cases, the most common regions involving gain of DNA copy number were 3q (n = 23; 51%), 8q (n = 21; 47%), and 1q (n = 14; 31%), and the most common regions with loss were 19 and 22 at 9 cases (20%) each, followed by 5q (n = 6; 13%). In multivariate analysis, the total number of genetic alterations was not associated with risk of recurrence, but gain in 5p was associated with a higher risk of recurrence (hazard ratio HR = 6.06, P = 0.0399), and gain in 1p as well as loss in 5q were associated with a significant decrease in recurrence (HR = 0.08, P = 0.0079, and HR = 0.10, P = 0.0143, respectively). Recurrence rate in patients with epithelial ovarian cancer is seemingly associated with specific genetic alterations detected by CGH, but the specific genes involved and the implications of these findings await further studies.

A case study involving four female patients inseminated with sperm samples from the same donor is reported. Routine amniocentesis of one of the patients revealed that the fetus is a carrier of a balanced reciprocal translocation, 46,XY,t(1;10)(q12;q11.2), which was subsequently detected in the donor. Counselled amniocentesis in the three remaining patients led to the detection of an additional translocation carrier fetus. All four pregnancies resulted in live births. Fluorescence in-situ hybridization was applied to identify normal, balanced or imbalanced sperm cells of the donor. Accordingly, routine karyotype analysis of sperm donors was introduced, and is now recommended in the authors' unit.

Velocardiofacial syndrome (VCFS) is characterized by both physical manifestations and neuropsychiatric disabilities. About 6–28% of cases are familial. The aim of the present study was to compare the clinical characteristics of subjects with familial and nonfamilial VCFS, with a special focus on cognitive and psychiatric disabilities. In addition, the complexities of coping with the disease in families in which both a parent and children are affected were highlighted in case vignettes. Sixteen patients from six families with VCFS were compared to 63 subjects with nonfamilial VCFS for physical parameters, IQ, and rate of major psychiatric disorders. After controlling for the effect of age, IQ was significantly lower in the familial compared to the nonfamilial group of VCFS patients. Rate of psychiatric disorders was similarly high in both groups. The familial group had fewer cardiac and palate anomalies. A significant negative correlation was found between IQ and age. Most of the adults with familial VCFS were neuropsychiatrically disabled. Thus, although familial VCFS seems to be associated with a milder physical phenotype than nonfamilial VCFS, the neuropsychiatric deficits are significant in both types, at all ages.

PURPOSE. To map the gene that causes brittle cornea syndrome (BCS). METHODS. Five patients from four families, all of Jewish Tunisian origin, were recruited into the study. Four of the five patients had red hair. DNA from the five patients and 104 control chromosomes was typed with seven 16q polymorphic markers surrounding the hair color gene, MCIR. RESULTS. A common haplotype in the homozygous state, comprising five markers spanning 4.7 Mb on chromosome 16q24, was found in all five patients but in none of the control subjects (P < 0.00001). CONCLUSIONS. The gene that causes BCS maps to a 4.7-Mb interval, between the markers D16S3423 and D16S3425 on 16q24.

Aims: To report on the clinical and metabolic characteristic and the unique chromosomal defect of a mentally retarded and morbidly obese patient. Methods: A 13-year follow-up, including insulin sensitivity, lipid profile and polysomnography studies and various therapeutic interventions are described. The presence of a supernumerary marker in karyotype preparation was further studied by fluorescence in situ hybridization (FISH). Comparative genomic hybridization (CGH) was used to identify the source of the chromosomal marker. Results: Insulin resistance was found by the homeostatic model assessment (HOMA) and the quantitative insulin sensitivity check index (QUICKI). M-FISH identified euchromatin derived from chromosome 19, and CGH confirmed the FISH results and demonstrated that the supernumerary marker derived from 19q12 to 19q13.2. Conclusion: The clinical and metabolic characteristics in association with partial chromosomal trisomy differ our patient from the currently known syndromes of obesity and mental retardation. The metabolic impairments in this case can derive from unbalanced expression of several genes in the 19q12–19q13.2 region, genes that are related to adipose tissue homeostasis and insulin resistance. The clinical and genetic similarities to a previously reported case may suggest that partial 19q trisomy is a new syndrome of obesity and mental retardation.

Velocardiofacial syndrome (VCFS) is caused by a microdeletion in chromosome 22 and is a risk factor for the development of schizophrenia and other psychiatric disorders. The catechol- O -methyltransferase ( COMT ), residing in the 22q11.2 microdeletion region, is a major candidate gene for genetic susceptibility to neuropsychiatric disorders in VCFS. Individuals with VCFS carrying the low-activity allele ( COMT L ) are expected to have the lowest possible COMT activity since they have only a single copy of the gene. We explored the possibility that COMT L is associated with psychiatric disorders commonly found in VCFS. Fifty-five unrelated individuals with VCFS underwent psychiatric evaluation and were genotyped for the COMT 158 Val/Met polymorphism coding for COMT high/low-activity alleles. The COMT L allele was significantly more prevalent in VCFS subjects with attention deficit hyperactivity disorder (ADHD) (73.9% vs. 33.3%, OR 5.67, χ2=7.76, p =0.005) and obsessive–compulsive disorder (OCD) (78.6% vs. 33.3%, OR 7.33, χ2=7.24, p =0.007) than in the control group (VCFS subjects without OCD, ADHD and schizophrenia/schizoaffective (SZ/SZaff) disorder). The results of this study suggest that greatly reduced COMT activity, as expected in VCFS COMT L individuals may be a risk factor for psychiatric sequelae in this population. Future longitudinal studies focusing on additional COMT polymorphic sites and other candidate genes from the deleted region will elucidate the molecular pathways leading to schizophrenia and other psychiatric disorders in VCFS.

The study of neurogenetic microdeletion syndromes provides an insight into the developmental psychopathology of psychiatric disorders. The aim of the study was to evaluate the prevalence of psychiatric disorders, especially obsessive-compulsive disorder (OCD), in patients with velocardiofacial syndrome (VCFS), a 22q11 microdeletion syndrome. Forty-three subjects with VCFS of mean age 18.3 ± 10.6 years were comprehensively assessed using semi-structured psychiatric interview and the Yale–Brown obsessive compulsive scale (Y-BOCS). Best estimate diagnoses were made on the basis of information gathered from subjects, parents, teachers, and social workers. Fourteen VCFS subjects (32.6%) met the DSM-IV criteria for OCD. OCD had an early age of onset and generally responded to fluoxetine treatment. It was not related to mental retardation. The most common obsessive-compulsive symptoms were contamination, aggression, somatic worries, hoarding, repetitive questions, and cleaning. Sixteen of the 43 patients (37.2%) had attention-deficit/hyperactivity disorder (ADHD), and 7 (16.2%) had psychotic disorder. The results of our study suggest that there is a strong association between VCFS and early-onset OCD. This finding may be significant in the understanding of the underlying genetic basis of OCD. © 2003 Wiley-Liss, Inc.

Epithelial ovarian cancer is the most lethal gynecologic malignancy in the western world. In 75% of patients, peritoneal metastases are found at the time of primary surgery. However, the genetic events leading to the development of ovarian tumors and to the genetic progression toward metastasis remain unclear. To gain insight into this issue, the types and patterns of DNA copy number changes were compared between primary ovarian tumors and their respective metastases by using comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). The genetic alterations (deletions and amplifications) detected by CGH were similar in the primary tumors and in their respective metastases. Moreover, the FISH results show a similar pattern of chromosomal abnormalities. Our results imply that the major gross genetic changes in ovarian cancer take place in the primary tumor, and the additional genetic changes that may occur in the metastases are not detectable by CGH.

Object. Craniopharyngioma is the most common childhood brain tumor and is thought to arise from embryonic remnants of the Rathke pouch. Some craniopharyngiomas are monoclonal in origin and hence presumably harbor somatic genetic alterations, although the precise molecular mechanisms involved in craniopharyngioma development are unknown. The goal of this study was to identify genetic alterations in craniopharyngiomas. Methods. To gain insight into the molecular mechanisms involved in development of these tumors, the authors analyzed nine adamantinomatous craniopharyngiomas by using comparative genomic hybridization. Six tumors (67%) displayed at least one genomic alteration, and three had six or more alterations. Only two tumors displayed a decrease in DNA copy number, and in all others an increase in DNA copy number was noted. Conclusions. The authors conclude that a subset of craniopharyngiomas consists of monoclonal tumors arising from activation of oncogenes located at specific chromosomal loci.

The aim of the study was to determine the rate of chromosome abnormalities in testicular sperm after intracytoplasmic sperm injection due to severe male factor infertility. The study groups included patient with non-obstructive azoospermia (n=9), obstructive azoospermia (n=10), Klinefelter's syndrome (n=5) and normal controls (n=6, groups I-VI, respectively). The mean serum levels of FSH 17.5+/-8.2 (P

Background Deletion of the entire steroid sulfatase (STS) gene is the most common molecular defect in X-linked ichthyosis (XLI) patients. Usually, additional flanking sequences are also missing. The aim of this study was to estimate the extent of deletions in an ethnically heterogeneous population of Israeli XLI patients. Methods Multiplex polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH) techniques were applied in the analysis of blood samples of 24 patients and amniotic cells of seven affected fetuses from 22 unrelated families. Results In 19 families, a large deletion of the 2–3 megabase was found. It included the whole STS gene and spanned adjacent areas up- and downstream between the loci DXS 1139 and DXS 1132. Two unrelated families of Iraqi ancestry had a partial deletion of the gene and its centromeric adjacent sequence. In another family, the telomeric end of the extragenic segment was only partially missing. Application of FISH on metaphase blood cells and interphase amniotic cells confirmed the diagnosis of XLI in all patients, except the three with partial intragenic deletion. In those cases, the remaining fraction of the gene was sufficient to provide a false negative result. Diagnosis of carriers and prenatal diagnosis in uncultured cells was applicable only by FISH. Conclusions Our study revealed a remarkable heterogeneity in the deletion pattern among Israeli patients with XLI. This heterogeneity could not be attributed to specific ethnic groups because of the small size of the study group. More studies involving patients of various ancestries should be carried out. In addition, this study demonstrated the usefulness of the FISH technique in the prenatal diagnosis of fetuses with suspected XLI.

We report on three cases of partial trisomy 2p in which the identification and exact localization of the duplicated chromosome segment was possible only by application of molecular cytogenetic techniques. These included fluorescence in situ hybridization by use of wcp2, N-myc, and subtelomeric 2p probes and comparative genomic hybridization with DNA isolated from blood samples, frozen fetal tendon, and formalin fixed, paraffin-embedded fetal lung tissue. Two of the cases concerned fetuses of gestational week 20 and 24 with duplication of nonoverlapping terminal (2pter--p24) and more proximal (2p25--p23) segments and with distinctly different phenotypes. The third case was due to a de novo inverted duplication of 2p25--p23, with loss of the subtelomeric region of 2p. This 53-month-old girl was a Bloom syndrome carrier. The patient had prenatal growth failure, borderline microcephaly, dilated lateral horns of the cerebral ventricles, transient cortical blindness, myopia, muscle hypotonia, and dilatation of the left renal collecting system. Dermal cysts were found on the glabella, the soles of both feet, and the vocal cord, causing respiratory embarrassment. Previously reported cases of pure trisomy 2p are reviewed, in an attempt to correlate clinical findings to overlapping regions in 2p. These cases illustrate the effectiveness of molecular cytogenetic methods in resolving subtle chromosomal aberrations in order to coordinate more accurately a chromosome regionspecific phenotype.

Congenital diaphragmatic hernia (CDH) is a relatively common malformation of unknown cause with high mortality due to hypoplasia of the lungs and pulmonary hypertension. We studied a family in which two fetuses had CDH, and two pregnancies resulted in first trimester missed abortions. Both fetuses with CDH had an apparently normal karyotype. In a subsequent pregnancy, fluorescent in situ hybridization analysis of amniocytes showed a balanced translocation 46,XY, t(5;15) (p15.3;q24) also present in the mother and in a normal child, suggesting that the diaphragmatic hernia in the first two fetuses was caused by a cryptic unbalanced translocation. This hypothesis is supported by a previous observation of CDH in a distal deletion of 15q as part of a multiple congenital anomalies syndrome. It is suggested that a gene distal to 15q21 is important for the normal development of the diaphragm.

In the last few years, attention has been focused on the use of interphase fluorescence in situ hybridization (FISH) for prenatal diagnosis with chromosome-specific DNA probes in the second trimester. This technique is accurate, rapid, and detects the most common aneuploidies. We present a preliminary study using FISH technique on uncultured amniotic cells derived from 30 fetuses with ultrasonographic evidence of intrauterine growth retardation (IUGR) in the third trimester. Fifteen fetuses were males and 15 were females. Seven fetuses (23.3%) had abnormal chromosomal constitution: five (18.6%) had trisomy 21, one (2.35%) had trisomy 18, and one (2.35%) showed a mosaic trisomy 18. No abnormalities were detected in the other 23 fetuses. Amniocentesis combined with FISH appears to be a safe, rapid, and accurate alternative to blood sampling in the third trimester, reducing the clinical and emotional stress of the time required to complete chromosome analysis by routine cytogenetics.