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Objectives Congenital adrenal hyperplasia (CAH) remains one of the most challenging endocrine disorders to diagnose, manage, and treat, especially in Africa where there is lack of neonatal screening program, and limited access to care. Data on biomolecular anomaly are sparse, therefore type of mutations are unknown, increasing management challenges and genetic counseling. The present study aims to describe clinical, biomolecular aspects of a group of Cameroonian patients. Methods We did an observational retrospective study at the pediatric endocrinology unit of the Mother and Child Centre of the Chantal Biya Foundation in Yaounde from May 2013 to December 2019, including all patients diagnosed with CAH. Results We consecutively included 31 patients aged less than 21 years, diagnosed CAH. Median age at diagnosis was 1.71 years (IQR 0.08–2.57 years). Abnormal genitalia was the main complain in 48.4%(n=15). The most prevalent genetic anomaly found in our study population (n=24) was on CYP11, found in 16 patients (66.6%) followed by CYP21A2 mutation found in 8 patients. Homozygous mutation of p.Q356X was found in half of patients with 11 hydroxylase deficiency. This mutation was mostly found in people from semi-Bantu tribes, declared non consanguineous. Conclusions 11 hydroxylase deficiency is the most prevalent form of CAH found in this group of Cameroonian children.

Resume But Le but de ce travail etait de rendre compte, apres dix annees de pratique, de notre experience de la genitoplastie feminisante chez l’enfant pre-pubere et l’adolescente presentant une anomalie du developpement genital (ADG) dans le contexte d’un pays en developpement. Materiels et methode Nous avons mene une etude observationnelle, descriptive et retrospective, allant du 1er novembre 2009 au 1er avril 2019, soit une periode de 9 ans. Ont ete inclus tous les enfants pre-puberes (8–12 ans) et les adolescentes elevees filles, porteuses d’une anomalie du developpement genital, desireuses de chirurgie ainsi que leurs familles et ayant ete l’objet d’une genitoplastie feminisante. Les parametres etudies ont ete : âge au moment de la presentation et de la chirurgie, diagnostic precis, gestes complementaires, suites operatoires, resultat cosmetique et recul. Pour chaque patient, la chirurgie n’a ete de mise qu’apres un diagnostic precis au sein d’une equipe multidisciplinaire experimentee. Les resultats cosmetiques prenaient en compte une reduction de la taille du clitoris et une ouverture separee de l’uretre et du vagin au perinee. Resultats Neufs enfants pre-puberes et adolescentes eleves filles d’âge median 8 ans (EI :10,75) ont ete colliges. L’âge median au moment de la chirurgie etait de 11 ans (EI : 9,5). Les diagnostics precis retenus ont ete : 46, XX ovotestis DSD elevee en fille (n = 2) ; 46, XY DSD insensibilite partielle aux androgenes (n = 2), 46, XY DSD deficit en 5 alpha reductase elevee fille (n = 1), 46, XY DSD deficit en 17-ceto-reductase elevee en fille (n = 1), 46, XY DSD dysgenesie gonadique (mutation du gene NR5A1) elevee en fille (n = 2) ; 45,X/46, XY dysgenesie gonadique mixte elevee en fille (n = 1). La gonadectomie a domine les gestes associes, bilaterale dans 7 cas et unilaterale gauche dans 2 cas. Avec un recul median de 26 mois (EI: 18,25), aucune complication hemorragique n’a ete notee, une retention aigue d’urine transitoire a pu etre observee et les resultats cosmetiques juges satisfaisants. Conclusion La genitoplastie feminisante au Cameroun reste un defi majeur pour le chirurgien pediatrique et elle ne doit se concevoir qu’apres un diagnostic precis. Le traditionnel retard porte a la consultation dans ce contexte apparait comme un avantage, puisqu’il permet aux patientes de participer aux decisions therapeutiques qui engagent leur avenir en termes de developpement psychosocial mais aussi de fertilite. Niveau de preuve 3.

Introduction According to the current classification of the Lawson Wilkins Pediatric Endocrine Society (LWPES) and the European Society for Pediatric Endocrinology (ESPE) of Disorders of Sex Development (DSD), etiologies vary around the world. Ethnic or genetic diversity probably explains this variability. We therefore conducted the present study on etiologies of DSDs in a country from central Africa. Methods We carried out an observational retrospective study at the Pediatric Endocrinology Unit of the Mother and Child Centre of the Chantal Biya Foundation in Yaounde, Cameroon from May 2013 to December 2019. All patients diagnosed with a DSD were included, and incomplete files excluded. Results We included 80 patients diagnosed with DSD during the study period. The 46,XX DSD were the most frequent in our study population (n = 41, 51.25%), with congenital adrenal hyperplasia (CAH) as the main diagnosis. The 46,XY DSD accounted for 33.75% and sex chromosome DSD group represented 15% of the study population. Conclusions DSDs are not an exceptional diagnosis in a Sub-Saharan context. 46,XX DSD are the most prevalent diagnosis in our setting. The diagnosis of all these affections is late compared to other centers, justifying advocacy for neonatal screening of DSDs in our context.

MECP2 duplication syndrome (MDS; OMIM 300260) is an X-linked neurodevelopmental disorder, caused by nonrecurrent duplications of the Xq28 region involving the gene methyl-CpG-binding protein 2 (MECP2; OMIM 300005). The core phenotype of affected individuals includes infantile hypotonia, severe intellectual disability, very poor-to-absent speech, progressive spasticity, seizures and recurrent infections. The condition is 100% penetrant in males, with observed variability in phenotypic expression within and between families. African patients with Xq28 duplication involving MECP2 have scarcely been reported. Here, we describe a sub-Saharan African male patient from Cameroon, with MDS caused by an inherited 610kb microduplication of Xq28 encompassing the genes MECP2, IRAK1, L1CAM and SLC6A8. This report supplements public data on MDS and contributes by highlighting the phenotype of this condition in affected individuals of African descent.

Mixed gonadal dysgenesis is characterised by unilateral chromosomal abnormality, which is probably the result of anaphase lag during mitosis. The 45, XO/46, XY karyotype is the most common form of mosaicism involving the Y chromosome. It is a rare clinical entity with a worldwide incidence of 1.5/10,000 live births. Its epidemiology in Sub-Saharan Africa is not known. This study reports experience in the management of 3 cases at the Yaounde Gynecologic-Obstetric and Paediatric Hospital. From November 2009 to November 2014, 3 cases were successfully managed at our institution. Results: All patients presented with asymmetrical gonadal differentiation. On one side of the body, a poorly-developed testicular gonad and on the other side a gonadal streak. A persistent Mόllerian remnant was equally found in the 3 cases. Management of mixed gonadal dysgenesis should be done in tertiary health care centres. A multidisciplinary team approach is recommended.

Williams-Beuren syndrome (WBS) is a rare neurodevelopmental condition caused by a recurrent chromosomal microdeletion involving about 28 contiguous genes at 7q11.23. Most patients display a specific congenital heart defect, characteristic facial features, a particular behavior, and intellectual disability. Cases from sub-Saharan Africa have been seldom reported. The present study describes 3 Cameroonian patients affected by WBS, aged 19 months, 13 and 14 years, in whom the diagnosis was confirmed by fluorescent in situ hybridization (FISH) and comparative genomic hybridization (CGH). The first patient presented with a congenital heart defect, the second and third with learning difficulties as well as developmental and behavioral issues. In the latter 2 cases, the facial phenotypes were similar to those of the unaffected population with the same ethnic background. However, the cardiovascular anomalies and friendly behavioral attitudes led to suspicion of WBS. FISH revealed the deletion of the WBS critical region in the first patient, and array-CGH detected a heterozygous ∼1.4-Mb deletion in the 7q11.23 region in the second and third patient. This preliminary report suggests that for sub-Saharan Africans clinical suspicion of WBS could be mostly based on behavioral phenotype and structural heart defects, and less on the classical facial dysmorphic signs.

Background: The 22q11.2 deletion syndrome is amongst the most common microdeletion syndrome in humans. Its prevalence remains unknown in sub-Saharan Africa, and its clinical features are underreported for people of African descent.Objective: We have investigated the prevalence of the 22q11.2 deletion syndrome in patients with congenital heart defects in Cameroon.Methods: A total of 70 of 100 cases of congenital cardiac malformation with echocardiographic evidence were examined prospectively and tested for the 22q11.2 deletion, using multiplex ligation-dependent probe amplification and fluorescence in situ hybridization.Results: Two of 70 patients (2.8%) were found to have 22q11.2 deletion. Both cases had conotruncal heart defects and exhibited extracardiac features of the 22q11.2 deletion syndrome that were either classical (e.g., puffy upper eyelids, bulbous tip of the nose) or less identifiable (telecanthus, hooding of eyelids and prominent nasal bridge).Conclusions: The report shows that the prevalence of the 22q11.2 deletion syndrome in patients with heart malformations in Cameroon (2.8%) is similar to that of various world populations. The clinical phenotypes will contribute to the Global Atlas for dysmorphology. “Omics” technologies offer much promise in genetic/genomic screening of severe global health problems.HighlightsThe 22q11.2 deletion syndrome is the most frequent microdeletion syndrome, among the most common genetic conditions in humans, and its prevalence is unknown in sub-Saharan Africa.Using multiplex ligation-dependent probe amplification (MLPA), and fluorescence in situ hybridization (FISH), we report that 2 of 70 patients (2.8%), Cameroonian children with congenital cardiac malformations, were found to have 22q11.2 deletion.Awareness should be raised by health practitioners for suspicion and screening of the 22q11.2 deletion syndrome, in patients with conotruncal malformations with or without craniofacial dysmorphism.The clinical features of the 2 cases presented here will contribute to the Global Atlas for dysmorphology, as very few studies are reported on dysmorphic signs in 22q11.2 deletion syndrome in individuals of African descent.OMICS technologies offer much promise in genetic/genomic screening of severe global health problems.

The aims of the present study were to assess (1) the parental origin of trisomy 21 and the stage in which nondisjunction occurs and (2) the relationship between altered genetic recombination and maternal age as risk factors for trisomy 21. The study included 102 cases with Down syndrome from the Croatian population. Genotyping analyses were performed by polymerase chain reaction using 11 short tandem repeat markers along chromosome 21q. The vast majority of trisomy 21 was of maternal origin (93%), followed by paternal (5%) and mitotic origin (2%). The frequencies of maternal meiotic I (MI) and meiotic II errors were 86% and 14%, respectively. The highest proportion of cases with zero recombination was observed among those with maternal MI derived trisomy 21. A higher proportion of telomeric exchanges were presented in cases with maternal MI errors and cases with young mothers, although these findings were not statistically significant. The present study is the first report examining parental origin and altered genetic recombination as a risk factor for trisomy 21 in a Croatian population. The results support that trisomy 21 has a universal genetic etiology across different human populations.

Background: SRY, located on the Y chromosome, is one of the key genes involved in human sex determination. SRY mutations are responsible for 10–15% of all cases of 46,XY gonadal dysgenesis (GD) but are rarely implicated in the pathogenesis of mixed GD. Methods: SRY was analyzed by sequence analysis of DNA extracted from blood leukocytes. SRY activity was evaluated by SOX9 immunostaining, one of the targets of SRY. Results: We report a case of mixed GD due to a novel SRY point mutation in a patient with a 46,XY karyotype, without mosaicism or submicroscopic genomic imbalances. Hormonal studies showed low anti-müllerian hormone and histological examination of the gonads showed a streak gonad on the right side and a left dysgenetic testis, thus permitting the diagnosis of mixed GD. Immunostaining for SOX9, a target of SRY, was positive in nuclei of Sertoli and epididymal cells in the left gonad and negative on the right, thus indicating asymmetric activation of SRY. Conclusion: Mixed GD can result from SRY mutations without mosaicism, neither in peripheral blood, nor within the gonads. The asymmetric effect of the point mutation implies the presence of local factors modulating SRY expression or action.

We report on two patients with de novo subtelomeric terminal deletion of chromosome 6p. Patient 1 is an 8-month-old female born with normal growth parameters, typical facial features of 6pter deletion, bilateral corectopia, and protruding tongue. She has severe developmental delay, profound bilateral neurosensory deafness, poor visual contact, and hypsarrhythmia since the age of 6 months. Patient 2 is a 5-year-old male born with normal growth parameters and unilateral hip dysplasia; he has a characteristic facial phenotype, bilateral embryotoxon, and moderate mental retardation. Further characterization of the deletion, using high-resolution array comparative genomic hybridization (array-CGH; Agilent Human Genome kit 244 K), revealed that Patient 1 has a 8.1 Mb 6pter-6p24.3 deletion associated with a contiguous 5.8 Mb 6p24.3-6p24.1 duplication and Patient 2 a 5.7 Mb 6pter-6p25.1 deletion partially overlapping with that of Patient 1. Complementary FISH and array analysis showed that the inv del dup(6) in Patient 1 originated de novo. Our results demonstrate that simple rearrangements are often more complex than defined by standard techniques. We also discuss genotype-phenotype correlations including previously reported cases of deletion 6p.

A 38-year-old male with primary infertility was referred for cytogenetic investigation. Karyotype analysis revealed a 46,XY,t(6;21)(p21.1;p13) translocation. The Ag-nucleolar organizer regions (NORs) banding technique demonstrated that the 21p NORs were retained in the derivative and actively transcribed. Family studies showed that three brothers, two sisters and their mother carried the t(6;21). All carrier males suffered from primary infertility with severe oligoasthenoteratospermia or azoospermia, whereas at least two of the three carrier women were fertile. The region of the translocation breakpoint was narrowed down cytogenetically and by fluorescence in situ hybridisation as 21p13 and 6p21.1. Southern blot analysis showed that the gene ZNF165, which maps to this region and which is specifically expressed in the testis, was not disrupted by the translocation. However, studies performed on testicular biopsy showed spermatocyte meiosis anomalies. We discuss the possible mechanisms by which the translocation might affect meiosis in spermatogenesis and lead to infertility.

OBJECTIVE: Previous studies linking the catechol O-methyltransferase (COMT) functional polymorphism to the specific phenotype in 22q11.2 deletion syndrome (22q11.2DS) have yielded inconsistent results. The goal of the present study was to replicate a recent finding that executive function is higher in individuals hemizygous for the Met allele. METHOD: Thirty-four children and young adults with a 22q11.2 microdeletion, hemizygous for the Val (N=14) or Met (N=20) polymorphism, were tested on measures of executive function, IQ, and memory. RESULTS: No significant differences were detected between Met- and Val-hemizygous participants on measures of executive function. The groups did not differ on full-scale, performance, and verbal IQ or on verbal and visual memory. CONCLUSIONS: These results suggest either a small effect of the COMT polymorphism on executive function in 22q11.2DS or no effect at all. Further research is needed to characterize the implications of hemizygosity of COMT in 22q11.2DS for cognitive function.

Velocardiofacial and DiGeorge syndromes, also known as 22q11.2 deletion syndrome (22q11DS), are congenital-anomaly disorders caused by a de novo hemizygous 22q11.2 deletion mediated by meiotic nonallelic homologous recombination events between low-copy repeats, also known as segmental duplications. Although previous studies exist, each was of small size, and it remains to be determined whether there are parent-of-origin biases for the de novo 22q11.2 deletion. To address this question, we genotyped a total of 389 DNA samples from 22q11DS-affected families. A total of 219 (56%) individuals with 22q11DS had maternal origin and 170 (44%) had paternal origin of the de novo deletion, which represents a statistically significant bias for maternal origin (p = 0.0151). Combined with many smaller, previous studies, 465 (57%) individuals had maternal origin and 345 (43%) had paternal origin, amounting to a ratio of 1.35 or a 35% increase in maternal compared to paternal origin (p = 0.000028). Among 1,892 probands with the de novo 22q11.2 deletion, the average maternal age at time of conception was 29.5, and this is similar to data for the general population in individual countries. Of interest, the female recombination rate in the 22q11.2 region was about 1.6-1.7 times greater than that for males, suggesting that for this region in the genome, enhanced meiotic recombination rates, as well as other as-of-yet undefined 22q11.2-specific features, could be responsible for the observed excess in maternal origin.

Opitz G/BBB Syndrome (OS) is a multiple congenital anomaly disorder characterized by developmental defects of midline structures. The most relevant clinical signs are ocular hypertelorism, hypospadias, cleft lip and palate, laryngo-tracheo-esophageal abnormalities, imperforate anus, and cardiac defects. Developmental delay, intellectual disability and brain abnormalities are also present. The X-linked form of this disorder is caused by mutations in the MID1 gene coding for a member of the tripartite motif family of E3 ubiquitin ligases. Here, we describe 12 novel patients that carry MID1 mutations emphasizing that laryngo-tracheo-esophageal defects are very common in OS patients and, together with hypertelorism and hypospadias, are the most frequent findings among the full spectrum of OS clinical manifestations. Besides missense and nonsense mutations, small insertions and deletions scattered along the entire length of the gene, we found that a consistent number of MID1 alterations are represented by the deletion of single coding exons. Deep characterization of one of these deletions reveals, for the first time within the MID1 gene, a complex rearrangement composed of two deletions, an inversion and a small insertion that may suggest the involvement of concurrent non-homologous mechanisms in the generation of the observed structural variant.

We report a male patient, offspring of a consanguineous marriage between first cousins, with cognitive impairment, autistic-like behavior, deafness, postaxial polydactyly, and mild dysmorphic features. aCGH revealed a 600 kb homozygous deletion of 4p15.1 (from 33.553 to 34.159 Mb in NCBI36 hg18) encoding several transcripts of unknown function. Both parents are heterozygous for the deletion and the non-affected brother is homozygous for the normal alleles. We hypothesize that this deletion is likely to contribute to the phenotype of the patient. This case underlines the contribution of aCGH in discovering potentially pathogenic CNVs in consanguineous matings.

0020-7292/$ – see front matter © 2011 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijgo.2011.08.020 [3] Holtgrave D, McGuire J. Impact of counseling in voluntary counseling and testing programs for persons at risk for or living with HIV infection. Clin Infect Dis 2007;45(Suppl 4):S240–3. [4] Hutchinson AB, Corbie-Smith G, Thomas SB, Mohanan S, del Rio C. Understanding the patient's perspective on rapid and routine HIV testing in an inner-city urgent care center. AIDS Educ Prev 2004;16(2):101–14.

Background Initiation of Prenatal Genetic Diagnosis (PND) has laid the foundation of the first medical genetic service in Cameroon. Method Cross-sectional descriptive study, illustrating some aspects of the genetic service using a small 24-months PND experience. Results The service began with a medical geneticist who had to follow-up the building and equipments supplies of the diagnosis laboratory; and to personally perform genetic consultations, molecular experiments and post-results counseling. PND was indicated for sickle cell disease ( SCD) in 33 cases (55%) and chromosomal anomalies in 27 cases (45%). With international collaboration, DNA analysis revealed 6 SCD-affected foetuses (20.7%); QF-PCR ( N = 25) and full karyotype ( N = 8) analysis revealed cases of trisomy 21 and trisomy 18. Following PND success, national effort granted more human and material resources to improve the service. The preliminary experience was made possible by three factors: 1) the availability of a trained Cameroonian medical geneticist 2) the availability of obstetricians trained in fetal medicine and 3) advocacy initiatives at national and international levels, which have proven invaluable for advice, training, sourcing of materials, and back-up reference diagnostic laboratory. Conclusion The practice of medical genetics, involving prenatal genetic diagnosis of sickle cell disease and chromosomal anomalies, is possible in Cameroon (sub-Saharan Africa).

Approximately 1.1 billion people currently live in countries where consanguineous marriages are customary, and among them one in every three marriages is between cousins. Opinions diverge between those warning of the possible health risks to offspring and others who highlight the social benefits of consanguineous marriages. A consanguinity study group of international experts and counselors met at the Geneva International Consanguinity Workshop from May 3 2010, to May 7, 2010, to discuss the known and presumptive risks and benefits of close kin marriages and to identify important future areas for research on consanguinity. The group highlighted the importance of evidence-based counseling recommendations for consanguineous marriages and of undertaking both genomic and social research in defining the various influences and outcomes of consanguinity. Technological advances in rapid high-throughput genome sequencing and for the identification of copy number variants by comparative genomic hybridization offer a significant opportunity to identify genotype-phenotype correlations focusing on autozygosity, the hallmark of consanguinity. The ongoing strong preferential culture of close kin marriages in many societies, and among migrant communities in Western countries, merits an equivalently detailed assessment of the social and genetic benefits of consanguinity in future studies. Genet Med 2011:13(9):841-847.

In 1990 we reported the case of a 17 years old girl with growth retardation, overweight and primary amenorrhea, presenting a de novo chromosomal rearrangement cytogenetically characterized as a paracentric inversion of the short arm of X chromosome 〚4〛 . The FISH analyses that were recently performed, revealed that in fact our patient presented a case of unbalanced translocation, 46,X, t(X;15)(p11.2; q15).

Current research in schizophrenia suggests that negative symptoms cannot be considered a unitary construct and should be divided in two dimensions: lack of motivation and impoverishment of expression. In addition, negative symptoms are particularly related to decreased daily-life functioning. In the present study, we aimed to replicate these results in a sample of participants with 22q11.2 deletion syndrome (22q11DS), a neurogenetic condition associated with high risk of developing schizophrenia. We also expected to observe an association between the COMT Val/Met polymorphism and negative symptoms. We examined the factorial structure of negative symptoms in a sample of 47 individuals with 22q11DS using the Structured Interview for Prodromal Symptoms (SIPS) and the Positive and Negative Syndrome Scale (PANSS). We also performed stepwise regression analyses to investigate the associations between negative symptoms, adaptive skills and the COMT Val/Met polymorphism. Negative symptoms were explained by a two-factor solution, namely the "amotivation and social withdrawal" and the "emotional withdrawal and expression" dimensions. The motivational dimension was significantly associated with daily-life functioning. Met carriers were rated as experiencing significantly more symptoms of amotivation. The results are interpreted in the light of existing cognitive models in the field of motivation and schizophrenia.

We report a case of materno-foetal transfusion in a phenotypically normal male foetus after death in utero at the 35th week of gestation. We have used cytogenetic and polymerase chain reaction (PCR) microsatellite analysis to determine the presence of maternal cells in foetal blood collected by intracardiac puncture. In the intracardiac blood sample, maternal cells were estimated to comprise between 5 and 10% of nucleated foetal blood cells. When there is a suspicion of foetal genetic pathology, it is necessary to be aware that the foetal blood karyotype may be misrepresentative, as the analysed blood cells can indeed be of maternal origin.

Down syndrome (DS) is one of the most frequent congenital birth defects, and the most common genetic cause of mental retardation. In most cases, DS results from the presence of an extra copy of chromosome 21. DS has a complex phenotype, and a major goal of DS research is to identify genotype-phenotype correlations. Cases of partial trisomy 21 and other HSA21 rearrangements associated with DS features could identify genomic regions associated with specific phenotypes. We have developed a BAC array spanning HSA21q and used array comparative genome hybridization (aCGH) to enable high-resolution mapping of pathogenic partial aneuploidies and unbalanced translocations involving HSA21. We report the identification and mapping of 30 pathogenic chromosomal aberrations of HSA21 consisting of 19 partial trisomies and 11 partial monosomies for different segments of HSA21. The breakpoints have been mapped to within approximately 85 kb. The majority of the breakpoints (26 of 30) for the partial aneuploidies map within a 10-Mb region. Our data argue against a single DS critical region. We identify susceptibility regions for 25 phenotypes for DS and 27 regions for monosomy 21. However, most of these regions are still broad, and more cases are needed to narrow down the phenotypic maps to a reasonable number of candidate genomic elements per phenotype.

PRINCIPLES: Human embryonic stem cells (hESC) hold enormous potential for regenerative medicine. So far, the majority of hESC lines have been derived from the isolated inner cell mass (ICM) of blastocysts of variable quality, and several of them from low-grade embryos. Moreover, most of the lines have been obtained in media containing animal components such as foetal bovine serum. We aimed to derive hESC lines in xeno-free conditions using spare embryos frozen in Switzerland before 2001. METHODS: In cooperation with Swiss IVF centres we collected up to 199 donated embryos frozen between 1988 and 2000 at different stages of development. RESULTS: Embryo quality at thawing showed wide variability, reduced quality and low survival upon culture. Using early arrested embryos (n=46), we report here the first Swiss hESC line, called CH-ES1, derived from a single blastomere of an arrested four-cell-stage embryo. Despite its polyploidy, already present at the third passage, CH-ES1 expressed ESC markers of pluripotency and differentiated into all three germ layers in embryoid bodies in vitro and in teratomas in vivo. CONCLUSIONS: As the destruction of viable developing embryos, even spare ones, raises serious ethical concerns, deriving hESC lines from arrested embryos may be an alternative approach to avoid embryo destruction. However, given the reduced derivation efficiency they should not be considered a unique and/or selective source of hESC lines.

We report on a de novo submicroscopic deletion of 20q13.33 identified by subtelomeric fluorescence in situ hybridization (FISH) in a 4-year-old girl with learning difficulties, hyperlaxity and strabismus, but without obvious dysmorphic features. Further investigations by array-based comparative genomic hybridization (array-CGH) and FISH analysis allowed us to delineate the smallest reported subterminal deletion of chromosome 20q, spanning a 1.1-1.6 Mb with a breakpoint localized between BAC RP5-887L7 and RP11-261N11. The genes CHRNA4 and KCNQ2 implicated in autosomal dominant epilepsy are included in the deletion interval. Subterminal 20q deletions as found in the present patient have, to our knowledge, only been reported in three patients. We review the clinical and behavioral phenotype of such "pure" subterminal 20q deletions.

The goals of the human genome project did not include sequencing of the heterochromatic regions. We describe here an initial sequence of 1.1 Mb of the short arm of human chromosome 21 (HSA21p), estimated to be 10% of 21p. This region contains extensive euchromatic-like sequence and includes on average one transcript every 100 kb. These transcripts show multiple inter- and intrachromosomal copies, and extensive copy number and sequence variability. The sequencing of the "heterochromatic" regions of the human genome is likely to reveal many additional functional elements and provide important evolutionary information. This work was supported by grants from the Swiss National Science Foundation (R.L., A.R., and S.E.A.), the NCCR Frontiers in Genetics (S.E.A.), the European Commission (BioSapiens NoE to R.G. and S.E.A. and AnEUploidy IP to A.R. and S.E.A.), Blanceflor-Boncompagni Ludovisi Foundation (P.P.) and ChildCare foundations (S.E.A.), a bilateral scientific and technological cooperation project between the University of Antwerp and Shanghai Chinese National Human Genome Centre (C.V.B. and S.-Y.W.), and NIH grant HG002385 (E.E.E.). E.E.E. is an investigator of the Howard Hughes Medical Institute

In human somatic cells, including T lymphocytes, telomeres progressively shorten with each cell division, eventually leading to a state of cellular senescence. Ectopic expression of telomerase results in the extension of their replicative life spans without inducing changes associated with transformation. However, it is yet unknown whether somatic cells that overexpress telomerase are physiologically indistinguishable from normal cells. Using CD8+ T lymphocyte clones overexpressing telomerase, we investigated the molecular mechanisms that regulate T cell proliferation. In this study, we show that early passage T cell clones transduced or not with human telomerase reverse transcriptase displayed identical growth rates upon mitogenic stimulation and no marked global changes in gene expression. Surprisingly, reduced proliferative responses were observed in human telomerase reverse transcriptase-transduced cells with extended life spans. These cells, despite maintaining high expression levels of genes involved in the cell cycle progression, also showed increased expression in several genes found in common with normal aging T lymphocytes. Strikingly, late passage T cells overexpressing telomerase accumulated the cyclin-dependent inhibitors p16Ink4a and p21Cip1 that have largely been associated with in vitro growth arrest. We conclude that alternative growth arrest mechanisms such as those mediated by p16Ink4a and p21Cip1 still remained intact and regulated the growth potential of cells independently of their telomere status.

In a search for potential infertility loci, which might be revealed by clustering of chromosomal breakpoints, we compiled 464 infertile males with a balanced rearrangement from Mendelian Cytogenetics Network database (MCNdb) and compared their karyotypes with those of a Danish nation-wide cohort. We excluded Robertsonian translocations, rearrangements involving sex chromosomes and common variants. We identified 10 autosomal bands, five of which were on chromosome 1, with a large excess of breakpoints in the infertility group. Some of these could potentially harbour a male-specific infertility locus. However, a general excess of breakpoints almost everywhere on chromosome 1 was observed among the infertile males: 26.5 versus 14.5% in the cohort. This excess was observed both for translocation and inversion carriers, especially pericentric inversions, both for published and unpublished cases, and was significantly associated with azoospermia. The largest number of breakpoints was reported in 1q21; FISH mapping of four of these breakpoints revealed that they did not involve the same region at the molecular level. We suggest that chromosome 1 harbours a critical domain whose integrity is essential for male fertility.

When sex chromosome abnormalities are detected by amniocentesis, the concerned couples have to face a difficult decision with regards to the pregnancy issue. Indeed the prognosis of these chromosomal abnormalities is favorable, developmental defects being generally not considered as severe. We have analysed 113 cases of sex chromosome abnormalities detected by amniocentesis and compared the pregnancy issues. The cases were obtained from the Centre Hospitalier de Chambéry and the Hôpitaux Universitaires de Genève. When such abnormalities are detected, the couple's decision can be variable, depending on many factors, as the country of origin. The goal of genetic counseling is to provide as many informations as possible to the concerned couples, in order to let them make an informed decision.

Gratacos et al. [2001: Cell 106:367-379] described an interstitial duplication dup(15)q24q26 (DUP25) in patients with anxiety disorders; this duplication was found in approximately 90% of patients and in 7% of controls. In order to determine if DUP25 is present in additional individuals susceptible to panic attacks, we tested 44 patients with anxiety disorders, using probes 251c23 and 216c14 mapping in the 15q24 and 15q26 region. We have not detected any DUP25. Our results suggest that DUP25 is not common in people with anxiety disorders in the population tested here.

This study reports the establishment of three major subtypes of human mesothelioma cells in tissue culture, i.e. the epithelioid, sarcomatoid and biphasic forms, and compares their phenotypic and biological characteristics. Primary cells isolated from biopsies or pleural exudates were subcultured for over 50 passages. We evaluated immunoreactivity using various mesothelial markers related to histological patterns of these cell lines. For epithelioid cells, calretinin and cytokeratin were found to be useful and easily interpretable markers as for control mesothelial cells. The biphasic form was only partially positive and the sarcomatoid type negative. Vimentin was expressed by all cell lines. BerEP4, a specific marker for adenocarcinoma, was negative. Interestingly, while the macrophage marker CD14 was negative, immunoreactivity for a mature macrophage marker (CD68) was expressed by all cell types, suggesting that this marker might constitute an additional tool useful in the differential diagnosis of mesothelioma. At the ultrastructural level, a cell surface rich in microvilli confirmed their mesothelial origin. PCR analysis revealed that none of the cell lines contained SV40 DNA. Karyotypic analyses showed more complex abnormalities in the epithelioid subtype than in the sarcomatoid form. These cell lines may be useful in the study of cellular, molecular and genetic aspects of the disease.

Objective: To report parental decisions regarding pregnancy termination following the prenatal diagnosis of a sex chromosome abnormality (SCA) in the fetus. Methods: Retrospective collection of data from records of 61 families receiving genetic counseling after prenatal diagnosis of a sex chromosome abnormality in the fetus in the Division of Medical Genetics, University Hospital of Geneva during the time period 1980–2001. Results: Among 61 couples with a prenatal diagnosis of a sex chromosome abnormality (SCA), 44 couples (72.1%) decided to terminate pregnancy. Pregnancy termination rates were 100, 73.9, 70, 50 and 42.9% for Turner syndrome, Klinefelter syndrome, 47,XXX females, 47,XYY males, and mosaic cases, respectively. In all 11 cases with a fetal abnormality seen on ultrasound, pregnancy was terminated. Termination rates were higher among couples with a higher mean number of previous children. Maternal age and year of test did not influence parental decisions. Conclusions: Parental decision to terminate a pregnancy for a fetus with a SCA varied by type of sex chromosome abnormality, by presence of fetal ultrasound anomalies, and by the mean number of previous children.

A well-documented case of non-mosaic Turner syndrome, with spontaneous pubertal development and ovulatory cycles is reported. Mosaicism could be excluded both by karyotyping of 172 metaphases of blood lymphocytes and fibroblasts, and by fluorescence in situ hybridization, using an X-centromeric probe, in 200 blood lymphocyte nuclei. This Turner syndrome patient underwent normal pubertal development, with spontaneous menarche at 14 years, followed by regular monthly periods. Hormonal measurements performed during puberty were consistent with the patient's pubertal development. At the age of 26 years the patient was referred for complete fertility evaluation. Detailed hormonal analyses were performed in a given cycle. They showed midluteal phase estradiol and progesterone values within the range corresponding to normal ovulation and corpus luteum function. In the same cycle, pelvic ultrasonography was also performed at days 13, 15 and 18. It demonstrated a spontaneous ovulation, with follicular rupture that occurred between days 15 and 18. This is the first report of a spontaneous ovulation in Turner syndrome evidenced, not only by hormonal analysis, but also by ultrasonographic demonstration of follicular rupture.

Background As children with velocardiofacial syndrome (VCFS) develop, they are at increased risk for psychopathology; one third will eventually develop schizophrenia. Because VCFS and the concomitant symptomatology result from a known genetic origin, the biological and behavioral characteristics of the syndrome provide an optimal framework for conceptualizing the associations among genes, brain development, and behavior. The purpose of this study was to investigate the effect of the parental origin of the 22q11.2 microdeletion on the brain development of children and adolescents with VCFS. Methods Eighteen persons with VCFS and 18 normal control subjects were matched individually for age and sex. Results of DNA polymorphism analyses determined the parental origin of the deletion. Nine persons with VCFS had a deletion on the maternally derived chromosome 22; 9 persons, on the paternally derived chromosome 22. High-resolution magnetic resonance imaging scans were analyzed to provide quantitative measures of gray and white matter brain tissue. Results Total brain volume was approximately 11% smaller in the VCFS group than in controls. Comparisons between VCFS subgroups (maternal vs paternal microdeletion 22q11.2) indicated a significant 9% volumetric difference in total volume of cerebral gray matter (volume was greater in patients with paternal microdeletion) but not cerebral white matter. Significant age-related changes in gray matter were detected for subjects whose 22q11.2 deletion was on the maternal chromosome. Conclusions Children and adolescents with VCFS experience major alterations in brain volumes. Significant reduction in gray matter development is attributable to presence of 22q11.2 microdeletion on the maternal chromosome.

Reprogramming somatic cells into a pluripotent state brings patient-tailored, ethical controversy-free cellular therapy closer to reality. However, stem cells and cancer cells share many common characteristics; therefore, it is crucial to be able to discriminate between them. We generated two induced pluripotent stem cell (iPSC) lines, with NANOG pre-transduction followed by OCT3/4, SOX2, and LIN28 overexpression. One of the cell lines, CHiPS W, showed normal pluripotent stem cell characteristics, while the other, CHiPS A, though expressing pluripotency markers, failed to differentiate and gave rise to germ cell-like tumours in vivo. Comparative genomic hybridisation analysis of the generated iPS lines revealed that they were genetically more stable than human embryonic stem cell counterparts. This analysis proved to be predictive for the differentiation potential of analysed cells. Moreover, the CHiPS A line expressed a lower ratio of p53/p21 when compared to CHiPS W. NANOG pre-induction followed by OCT3/4, SOX2, MYC, and KLF4 induction resulted in the same tumour-inducing phenotype. These results underline the importance of a re-examination of the role of NANOG during reprogramming. Moreover, this reprogramming method may provide insights into primordial cell tumour formation and cancer stem cell transformation.

Malignant melanomas are characterized by increased karyotypic complexity, extended aneuploidy and heteroploidy. We report a melanoma metastasis to the peritoneal cavity with an exceptionally stable, abnormal pseudodiploid karyotype as verified by G-Banding, subtelomeric, centromeric and quantitative Fluorescence in Situ Hybridization (FISH). Interestingly this tumor had no detectable telomerase activity as indicated by the Telomere Repeat Amplification Protocol. Telomeric Flow-FISH and quantitative telomeric FISH on mitotic preparations showed that malignant cells had relatively short telomeres. Microsatellite instability was ruled out by the allelic pattern of two major mononucleotide repeats. Our data suggest that a combination of melanoma specific genomic imbalances were sufficient and enough for this fatal tumor progression, that was not accompanied by genomic instability, telomerase activity, or the engagement of the alternative recombinatorial telomere lengthening pathway.