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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.

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.

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.

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.

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 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.

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.

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.

Background: To open vaginal cavity to the pelvic floor is part of surgical treatment for urogenital sinus (UGS) in girls with congenital adrenal hyperplasia (CAH). For high UGS, this operative procedure can be challenging and may jeopardise urinary continence. Combined perineal and laparoscopic approaches could be useful to minimise perineal dissection and to facilitate the vaginal lowering. Patients and Methods: We report the procedure of a laparoscopic-assisted vaginal pull-through for supra-sphincteric UGS in a 5-year-old girl with CAH. Laparoscopic dissection of the vagina from the posterior wall of the bladder and urethra, division of the confluence and vaginal pull-through to the perineum are described. Discussion: The technique is derived from laparoscopic-assisted treatment for high ano-rectal malformations. Compared with current procedures for treatment for high UGS, laparoscopic-assisted approach allows mobilising vagina with minimal dissection of perineum and complete preservation of urethra. Another major advantage is to provide a direct vision for dissection of the space between rectum and urethra prior to vaginal pull-through. Conclusion: Laparoscopic-assisted vaginal pull-through appears to be an interesting approach for high UGS in CAH patients, reducing dissection and risk of urinary incontinence. This new approach needs to be strengthened by other cases.

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.