Reversible encephalitis-like episodes in fragile X-associated tremor/ataxia syndrome: a case report.

BACKGROUND: Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by CGG repeat expansion of FMR1 gene. Both FXTAS and neuronal intranuclear inclusion disease (NIID) belong to polyglycine diseases and present similar clinical, radiological, and pathological features, making it difficult to distinguish these diseases. Reversible encephalitis-like attacks are often observed in NIID. It is unclear whether they are presented in FXTAS and can be used for differential diagnosis of NIID and FXTAS. CASE PRESENTATION: A 63-year-old Chinese male with late-onset gait disturbance, cognitive decline, and reversible attacks of fever, consciousness impairment, dizziness, vomiting, and urinary incontinence underwent neurological assessment and examinations, including laboratory tests, electroencephalogram test, imaging, skin biopsy, and genetic test. Brain MRI showed T2 hyperintensities in middle cerebellar peduncle and cerebrum, in addition to cerebellar atrophy and DWI hyperintensities along the corticomedullary junction. Lesions in the brainstem were observed. Skin biopsy showed p62-positive intranuclear inclusions. The possibilities of hypoglycemia, lactic acidosis, epileptic seizures, and cerebrovascular attacks were excluded. Genetic analysis revealed CGG repeat expansion in FMR1 gene, and the number of repeats was 111. The patient was finally diagnosed as FXTAS. He received supportive treatment as well as symptomatic treatment during hospitalization. His encephalitic symptoms were completely relieved within one week. CONCLUSIONS: This is a detailed report of a case of FXTAS with reversible encephalitis-like episodes. This report provides new information for the possible and rare features of FXTAS, highlighting that encephalitis-like episodes are common in polyglycine diseases and unable to be used for differential diagnosis.

Carrier Screening Programs for Cystic Fibrosis, Fragile X Syndrome, Hemoglobinopathies and Thalassemia, and Spinal Muscular Atrophy: A Health Technology Assessment.

Background: We conducted a health technology assessment to evaluate the safety, effectiveness, and cost-effectiveness of carrier screening programs for cystic fibrosis (CF), fragile X syndrome (FXS), hemoglobinopathies and thalassemia, and spinal muscular atrophy (SMA) in people who are considering a pregnancy or who are pregnant. We also evaluated the budget impact of publicly funding carrier screening programs, and patient preferences and values. Methods: We performed a systematic literature search of the clinical evidence. We assessed the risk of bias of each included study using the Cochrane Risk of Bias tool and the Risk of Bias Assessment tool for Non-randomized Studies (RoBANS), and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic economic literature search and conducted cost-effectiveness analyses comparing preconception or prenatal carrier screening programs to no screening. We considered four carrier screening strategies: 1) universal screening with standard panels; 2) universal screening with a hypothetical expanded panel; 3) risk-based screening with standard panels; and 4) risk-based screening with a hypothetical expanded panel. We also estimated the 5-year budget impact of publicly funding preconception or prenatal carrier screening programs for the given conditions in Ontario. To contextualize the potential value of carrier screening, we spoke with 22 people who had sought out carrier screening. Results: We included 107 studies in the clinical evidence review. Carrier screening for CF, hemoglobinopathies and thalassemia, FXS, and SMA likely results in the identification of couples with an increased chance of having an affected pregnancy (GRADE: Moderate). Screening likely impacts reproductive decision-making (GRADE: Moderate) and may result in lower anxiety among pregnant people, although the evidence is uncertain (GRADE: Very low).We included 21 studies in the economic evidence review, but none of the study findings were directly applicable to the Ontario context. Our cost-effectiveness analyses showed that in the short term, preconception or prenatal carrier screening programs identified more at-risk pregnancies (i.e., couples that tested positive) and provided more reproductive choice options compared with no screening, but were associated with higher costs. While all screening strategies had similar values for health outcomes, when comparing all strategies together, universal screening with standard panels was the most cost-effective strategy for both preconception and prenatal periods. The incremental cost-effectiveness ratios (ICERs) of universal screening with standard panels compared with no screening in the preconception period were $29,106 per additional at-risk pregnancy detected and $367,731 per affected birth averted; the corresponding ICERs in the prenatal period were about $29,759 per additional at-risk pregnancy detected and $431,807 per affected birth averted.We estimated that publicly funding a universal carrier screening program in the preconception period over the next 5 years would require between $208 million and $491 million. Publicly funding a risk-based screening program in the preconception period over the next 5 years would require between $1.3 million and $2.7 million. Publicly funding a universal carrier screening program in the prenatal period over the next 5 years would require between $128 million and $305 million. Publicly funding a risk-based screening program in the prenatal period over the next 5 years would require between $0.8 million and $1.7 million. Accounting for treatment costs of the screened health conditions resulted in a decrease in the budget impact of universally provided carrier screening programs or cost savings for risk-based programs.Participants value the perceived potential positive impact of carrier screening programs such as medical benefits from early detection and treatment, information for reproductive decision-making, and the social benefit of awareness and preparation. There was a strong preference expressed for thorough, timely, unbiased information to allow for informed reproductive decision-making. Conclusions: Carrier screening for CF, FXS, hemoglobinopathies and thalassemia, and SMA is effective at identifying at-risk couples, and test results may impact preconception and reproductive decision-making.The cost-effectiveness and budget impact of carrier screening programs are uncertain for Ontario. Over the short term, carrier screening programs are associated with higher costs, and also higher chances of detecting at-risk pregnancies compared with no screening. The 5-year budget impact of publicly funding universal carrier screening programs is larger than that of risk-based programs. However, accounting for treatment costs of the screened health conditions results in a decrease in the total additional costs for universal carrier screening programs or in cost savings for risk-based programs.The people we spoke with who had sought out carrier screening valued the potential medical benefits of early detection and treatment, particularly the support and preparation for having a child with a potential genetic condition.

Reproductive genetic carrier screening for cystic fibrosis, fragile X syndrome and spinal muscular atrophy: patterns of community and healthcare provider participation in a Victorian screening program.

BACKGROUND: The Royal Australian and New Zealand College of Obstetricians and Gynaecologists and The Royal Australian College of General Practice recommend that information on carrier screening for at least the most common inherited genetic conditions in our population, that is, thalassaemia, cystic fibrosis (CF), spinal muscular atrophy (SMA), and fragile X syndrome (FXS), should be offered to all women planning pregnancy or in early pregnancy regardless of family history or ethnicity. The aim of this study was to investigate patterns of participation by healthcare providers (HCP) and the community in screening. METHODS: Participation in a Victorian program screening for CF, SMA and FXS between September 2013 and October 2018 was analysed. Requesting HCP and patient data were extracted from screening request forms. Data were analysed with respect to profession of requesting HCP, and characteristics of women screened (age, pregnancy status, socioeconomic status, geographic location, and family history of CF, SMA or FXS). In total, 21 172 women and 1288 HCPs participated in the program over this period. RESULTS: There was a steep socioeconomic gradient in screening uptake, with nearly half the women screened (10 349) being in the highest socioeconomic quintile. The screening rate was much higher in metropolitan areas than in regional areas. Obstetricians made most of the requests for screening, whereas 20% of requests were by GPs. Most participating GPs only made a single screening request (78%) and very few GPs made >100 screening requests compared with obstetricians (0.2% vs 17%). GPs were more likely to screen women before pregnancy compared with obstetricians (47% vs 11%). Approximately 1.5% of Victorian women of child-bearing age and 3% of pregnant Victorian women were screened by this program over the period of this study. CONCLUSION: This study highlights the translation gap between recommendations and practice, with marked inequity of access to reproductive genetic carrier screening in relation to socioeconomic status and geography. Increased participation by GPs could improve community access to reproductive genetic carrier screening, particularly access to preconception screening. Addressing the causes of inequity of access will allow more women and couples the opportunity to make informed choices about participation in screening.

Combined Hamartoma of the Retina and Retinal Pigment Epithelium in a Patient With Fragile X Syndrome.

A 13-year-old boy with fragile X syndrome presented with painless, decreased vision in his right eye. Funduscopy revealed fibrotic tissue and an epiretinal membrane. This patient with fragile X syndrome was diagnosed as having combined hamartoma of the retina and retinal pigment epithelium and treated with vitrectomy and epiretinal membrane peeling. [J Pediatr Ophthalmol Strabismus. 2022;59(4):e39-e41.].

A case of idiopathic normal pressure hydrocephalus with fragile X-associated tremor/ataxia syndrome.

Clinical management of patients with fragile X-associated tremor/ataxia syndrome (FXTAS) is a challenge, and there has been not an established treatment for FXTAS, which is now treated symptomatically. Diagnosis of coexistent idiopathic normal pressure hydrocephalus (iNPH) with FXTAS is also hard because clinical and imaging features can overlap between the FXTAS patients coexistent with and without iNPH. We present a 79-year-old male genetically diagnosed with FXTAS who was successfully treated by a shunt surgery and consequently diagnosed with iNPH, and suggest the management of coexistent iNPH with FXTAS when it is clinically suspicious.

What is the threshold of mature oocytes to obtain at least one healthy transferable cleavage-stage embryo after preimplantation genetic testing for fragile X syndrome?

STUDY QUESTION: What are the chances of obtaining a healthy transferable cleavage-stage embryo according to the number of mature oocytes in fragile X mental retardation 1 (FMR1)-mutated or premutated females undergoing preimplantation genetic testing (PGT)? SUMMARY ANSWER: In our population, a cycle with seven or more mature oocytes has an 83% chance of obtaining one or more healthy embryos. WHAT IS KNOWN ALREADY: PGT may be an option to achieve a pregnancy with a healthy baby for FMR1 mutation carriers. In addition, FMR1 premutation is associated with a higher risk of diminished ovarian reserve and premature ovarian failure. The number of metaphase II (MII) oocytes needed to allow the transfer of a healthy embryo following PGT has never been investigated. STUDY DESIGN, SIZE, DURATION: The study is a monocentric retrospective observational study carried out from January 2006 to January 2020 that is associated with a case-control study and that analyzes 38 FMR1 mutation female carriers who are candidates for PGT; 16 carried the FMR1 premutation and 22 had the full FMR1 mutation. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 95 controlled ovarian stimulation (COS) cycles for PGT for fragile X syndrome were analyzed, 49 in premutated patients and 46 in fully mutated women. Only patients aged ≤38 years with anti-Müllerian hormone (AMH) >1 ng/ml and antral follicle count (AFC) >10 follicles were eligible for the PGT procedure. Each COS cycle of the FMR1-PGT group was matched with the COS cycles of partners of males carrying any type of translocation (ratio 1:3). Conditional logistic regression was performed to compare the COS outcomes. We then estimated the number of mature oocytes needed to obtain at least one healthy embryo after PGT using receiver operating characteristic curve analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, in the FMR1-PGT group, the median number of retrieved and mature oocytes per cycle was 11 (interquartile range 7-15) and 9 (6-12), respectively. The COS outcomes of FMR1 premutation or full mutation female carriers were not altered compared with the matched COS cycles in partners of males carrying a balanced translocation in their karyotype. Among the 6 (4-10) Day 3 embryos obtained in the FMR1-PGT group, a median number of 3 (1-6) embryos were morphologically eligible for biopsy, leading to 1 (1-3) healthy embryo. A cutoff value of seven MII oocytes yielded a sensitivity of 82% and a specificity of 61% of having at least one healthy embryo, whereas a cutoff value of 10 MII oocytes led to a specificity of 85% and improved positive predictive value. LIMITATIONS, REASONS FOR CAUTION: This study is retrospective, analyzing a limited number of cycles. Moreover, the patients who were included in a fresh PGT cycle were selected on ovarian reserve parameters and show high values in ovarian reserve tests. This information could influence our conclusion. WIDER IMPLICATIONS OF THE FINDINGS: The results relate only to the target population of this study, with a correct ovarian reserve of AMH >1 and AFC >10. However, the information provided herein extends knowledge about the current state of COS for FMR1 mutation carriers in order to provide patients with proper counseling regarding the optimal number of oocytes needed to have a chance of transferring an unaffected embryo following PGT. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: N/A.

[Cancer in children with intellectual disabilities: Questioning and ethical issues]. / Cancer chez un enfant porteur de handicap intellectuel : questionnement et enjeux éthiques.

The Parents and Caregivers group in the face of ethics in pediatrics of the Île-de-France Ethics Area wondered about the association of the words Disability and Cancer by focusing on the study of the course of children with intellectual disability, treated for cancer. These situations are exceptional, the number of cases in France must not be more than fifty per year. We gathered the testimony of five families of children using a semi-directive survey taking up the journey from birth, announcement of the handicap, the diagnosis of cancer and its treatment. The verbatim show that each story is unique and rich in lessons, despite the feeling of "double penalty": "He did not deserve this, a handicap plus cancer is a lot for one person", "the shot moreover." A healthcare team was also interviewed and raised an additional question: "First, the double penalty… then, what's the point?" Through these testimonies, we sought to question the ethical principles of care, which can be shaken up in these extraordinary supported.

Detection of Cryptic Fragile X Full Mutation Alleles by Southern Blot in a Female and Her Foetal DNA via Chorionic Villus Sampling, Complicated by Mosaicism for 45,X0/46,XX/47,XXX.

We describe a female with a 72 CGG FMR1 premutation (PM) (CGG 55-199) and family history of fragile X syndrome (FXS), referred for prenatal testing. The proband had a high risk of having an affected pregnancy with a full mutation allele (FM) (CGG > 200), that causes FXS through hypermethylation of the FMR1 promoter. The CGG sizing analysis in this study used AmplideX triplet repeat primed polymerase chain reaction (TP-PCR) and long-range methylation sensitive PCR (mPCR). These methods detected a 73 CGG PM allele in the proband's blood, and a 164 CGG PM allele in her male cultured chorionic villus sample (CVS). In contrast, the Southern blot analysis showed mosaicism for: (i) a PM (71 CGG) and an FM (285-768 CGG) in the proband's blood, and (ii) a PM (165 CGG) and an FM (408-625 CGG) in the male CVS. The FMR1 methylation analysis, using an EpiTYPER system in the proband, showed levels in the range observed for mosaic Turner syndrome. This was confirmed by molecular and cytogenetic karyotyping, identifying 45,X0/46,XX/47,XXX lines. In conclusion, this case highlights the importance of Southern blot in pre- and postnatal testing for presence of an FM, which was not detected using AmplideX TP-PCR or mPCR in the proband and her CVS.

Síndrome del X frágil en fecundación in vitro: reporte de caso / Fragile X syndrome in in vitro fertilization: a case report

INTRODUCCIÓN: El síndrome de X frágil (SXF) es la primera causa heredable de discapacidad intelectual y autismo. Mujeres con la premutación del gen FMR1, relacionado con SXF, suelen ser asintomáticas, pero pueden tener hijos afectados. Se reporta un caso de SXF producto de fecundación in vitro con óvulos de una donante portadora de la premutación del FMR1. DESCRIPCIÓN DEL CASO: Pareja que requirió reproducción asistida dado que la mujer tenía antecedente de hipofisectomía; se realizó fecundación in vitro con óvulo donado, lográndose un embarazo gemelar. El gemelo femenino fue diagnosticado a los 2 años de edad con mutación completa del gen FMR1 y SXF, y la donante de óvulos, quien era asintomática, fue posteriormente confirmada como portadora de la premutación del FMR1. DISCUSIÓN: El protocolo de evaluación del riesgo de heredar enfermedades genéticas para donantes de óvulos se limita al cariotipo bandas G. Esta prueba no analiza alteraciones genéticas de herencia recesiva. Mediante secuenciación de nueva generación se podrían identificar portadoras de variantes alélicas patogénicas en estado de heterocigosis. Las mujeres con premutación del FMR1, tienen un riesgo del 50% de transmitir el alelo anormal a sus descendientes en cada embarazo, y estos de ser afectados por el SXF; por tanto, la asesoría genética es requerida en estos casos. CONCLUSIÓN: Los donantes de gametos deberían ser evaluados mediante pruebas moleculares para detección de variantes alélicas que pudieran ser transmitidas a sus gametos, y que pudieran generar enfermedades genéticas en los embarazos a partir de ellos.

INTRODUCTION: Fragile X syndrome (SXF) is the lead hereditary cause of intellectual disability and autism. Women with premutation in FMR1 gene, related to SXF, are usually asymptomatic, but they could have affected children. We report a case of SXF, product of an in vitro fertilization, secondary to an egg donation from a carrier of the premutation in the FMR1 gene. DESCRIPTION OF THE CASE: A couple required assisted reproduction because the woman had antecedent of hypophysectomy. An in vitro fertilization was done using a donated egg, achieving a twin pregnancy. The female twin was diagnosed with full mutation in the FMR1 gene and SXF by her second year of age. Donor woman, who was asymptomatic, was found to be a carrier of the premutation for SXF. DISCUSSION: The protocols to evaluate the risk of inherit genetic diseases for egg donors stint to band G karyotypes, which don—t consider genetic alterations with recessive inheritance pattern. Next generation sequencing allows to identify carriers of allelic heterozygote variations related with pathology. Women with the premutation in FMR1 have a risk of 50%, in each pregnancy, to pass down an affected allele to their offspring, who would be affected by SXF. Genetic counseling is mandatory in that cases. CONCLUSION: Gamete donor candidates should be submitted to molecular tests to identify allelic variants that could be inherited to the recipient offspring and cause genetic diseases.

Características físicas e bucais na síndrome do X frágil: revisão de literatura / Physical and oral characteristics of fragile X syndrome: literature review

Introdução: A síndrome do cromossomo X frágil é uma síndrome genética que acomete principalmente indivíduos do sexo masculino. O nome desta síndrome ocorre como consequência de um estreitamento da extremidade distal do braço longo do cromossomo X, local chamado de sítio frágil. O presente trabalho apresenta uma revisão de literatura, apresentando etiologia, prevalência, métodos de diagnósti-co, características comportamentais, características físicas gerais e de interesse odontológico, além das considerações acerca do atendimento, realizado pelo cirurgião-dentista, em portadores da síndrome do X frágil. Revisão de literatura: As principais características comportamentais são o déficit de atenção, a dificuldade na interação social, a timidez, a ansiedade, a labilidade emocional e os movimentos este-reotipados de mãos. Os achados de interesse odontológico mais prevalentes na literatura foram palato ogival, prog-natismo mandibular, macroglossia, hipoplasia de esmalte e má oclusão. Discussão: Não foram encontrados muitos artigos voltados para a análise facial e odontológica destes pacientes. O atendimento deste público é um desafio para o cirurgião-dentista devido às características comportamentais e fisiológicas apresentadas. Conclusão: o conhecimento das características desta síndrome pelo profissional é impor-tante, pois a síndrome comumente se associa à doenças sistêmicas que podem influenciar no plano de tratamento, além de alterações orofaciais importantes.

Introduction: The fragile X syndrome is a genetic syn-drome that mainly affects males. The name of this syn-drome occurs as a consequence of a narrowing of the distal end of the long arm of the X chromosome, a site called the fragile site. This paper presents a review of the literature, presenting etiology, prevalence, diagnostic methods, behavioral characteristics, general physical characteristics and dental interest, as well as considera-tions about the care provided by the dentist in patients with fragile X syndrome. Literature review: The main behavioral characteristics are attention deficit, difficulty in social interaction, shyness, anxiety, emotional lability and stereotyped hand movements. The most prevalent findings of dental interest in the literature were the ogival palate, mandibular prognathism, macroglossia, enamel hypoplasia and malocclusion. Discussion: There were not many articles focused on facial and dental analysis of these patients. The care of this public is a challenge for the dentist due to the behavioral and physiological characteristics presented. Conclusion: professional know-ledge of the characteristics of this syndrome is important, as the syndrome is commonly associated with systemic diseases that may influence the treatment plan, as well as major orofacial changes.

Clinical experience with carrier screening in a general population: support for a comprehensive pan-ethnic approach.

PURPOSE: To present results from a large cohort of individuals receiving expanded carrier screening (CS) in the United States. METHODS: Single-gene disorder carrier status for 381,014 individuals was determined using next-generation sequencing (NGS) based CS for up to 274 genes. Detection rates were compared with literature-reported values derived from disease prevalence and carrier frequencies. Combined theoretical affected pregnancy rates for the 274 screened disorders were calculated. RESULTS: For Ashkenazi Jewish (AJ) diseases, 81.6% (4434/5435) of carriers identified did not report AJ ancestry. For cystic fibrosis, 44.0% (6260/14,229) of carriers identified had a variant not on the standard genotyping panel. Individuals at risk of being a silent spinal muscular atrophy carrier, not detectable by standard screening, comprised 1/39 (8763/344,407) individuals. For fragile X syndrome, compared with standard premutation screening, AGG interruption analysis modified risk in 83.2% (1128/1356) premutation carriers. Assuming random pairing across the study population, approximately 1/175 pregnancies would be affected by a disorder in the 274-gene screening panel. CONCLUSION: Compared with standard screening, NGS-based CS provides additional information that may impact reproductive choices. Pan-ethnic CS leads to substantially increased identification of at-risk couples. These data support offering NGS-based CS to all reproductive-aged women.

Síndrome X frágil: presentación clínica, patología y tratamiento / Fragile X syndrome: clinical presentation, pathology and treatment

Resumen El síndrome X frágil es la condición monogenética que produce más casos de autismo y de discapacidad intelectual. La repetición de tripletes CGG (> 200) y su metilación conllevan el silenciamiento del gen FMR1. La proteína FMRP (producto del gen FMR1) interacciona con los ribosomas, controlando la traducción de mensajeros específicos y su pérdida produce alteraciones de la conectividad sináptica. El tamizaje de síndrome X frágil se realiza por reacción en cadena de la polimerasa. La recomendación actual de la Academia Americana de Pediatría es realizar pruebas a quienes presenten discapacidad intelectual, retraso global del desarrollo o antecedentes familiares de afección por la mutación o premutación. Países hispanos como Colombia, Chile y España reportan altas prevalencias de síndrome X frágil y han creado asociaciones o corporaciones nacionales de X frágil que buscan acercar a los pacientes a redes disponibles de diagnóstico y tratamiento.

Abstract Fragile X syndrome is the monogenetic condition that produces more cases of autism and intellectual disability. The repetition of CGG triplets (> 200) and their methylation entail the silencing of the FMR1 gene. The FMRP protein (product of the FMR1 gene) interacts with ribosomes by controlling the translation of specific messengers, and its loss causes alterations in synaptic connectivity. Screening for fragile X syndrome is performed by polymerase chain reaction. Current recommendation of the American Academy of Pediatrics is to test individuals with intellectual disability, global developmental retardation or with a family history of presence of the mutation or premutation. Hispanic countries such as Colombia, Chile and Spain report high prevalence of fragile X syndrome and have created fragile X national associations or corporations that seek to bring patients closer to available diagnostic and treatment networks.

Population genomic screening of all young adults in a health-care system: a cost-effectiveness analysis.

PURPOSE: To consider the impact and cost-effectiveness of offering preventive population genomic screening to all young adults in a single-payer health-care system. METHODS: We modeled screening of 2,688,192 individuals, all adults aged 18-25 years in Australia, for pathogenic variants in BRCA1/BRCA2/MLH1/MSH2 genes, and carrier screening for cystic fibrosis (CF), spinal muscular atrophy (SMA), and fragile X syndrome (FXS), at 71% testing uptake using per-test costs ranging from AUD$200 to $1200 (~USD$140 to $850). Investment costs included genetic counseling, surveillance, and interventions (reimbursed only) for at-risk individuals/couples. Cost-effectiveness was defined below AUD$50,000/DALY (disability-adjusted life year) prevented, using an incremental cost-effectiveness ratio (ICER), compared with current targeted testing. Outcomes were cancer incidence/mortality, disease cases, and treatment costs reduced. RESULTS: Population screening would reduce variant-attributable cancers by 28.8%, cancer deaths by 31.2%, and CF/SMA/FXS cases by 24.8%, compared with targeted testing. Assuming AUD$400 per test, investment required would be between 4 and 5 times higher than current expenditure. However, screening would lead to substantial savings in medical costs and DALYs prevented, at a highly cost-effective ICER of AUD$4038/DALY. At AUD$200 per test, screening would approach cost-saving for the health system (ICER = AUD$22/DALY). CONCLUSION: Preventive genomic screening in early adulthood would be highly cost-effective in a single-payer health-care system, but ethical issues must be considered.

Reproductive genetic carrier screening for cystic fibrosis, fragile X syndrome, and spinal muscular atrophy in Australia: outcomes of 12,000 tests.

PurposeTo describe our experience of offering simultaneous genetic carrier screening for cystic fibrosis (CF), fragile X syndrome (FXS), and spinal muscular atrophy (SMA).MethodsCarrier screening is offered through general practice, obstetrics, fertility, and genetics settings before or in early pregnancy. Carriers are offered genetic counseling with prenatal/preimplantation genetic diagnosis available to those at increased risk.ResultsScreening of 12,000 individuals revealed 610 carriers (5.08%; 1 in 20): 342 CF, 35 FXS, 241 SMA (8 carriers of 2 conditions), approximately 88% of whom had no family history. At least 94% of CF and SMA carriers' partners were tested. Fifty couples (0.42%; 1 in 240) were at increased risk of having a child with one of the conditions (14 CF, 35 FXS, and 1 SMA) with 32 pregnant at the time of testing. Of these, 26 opted for prenatal diagnosis revealing 7 pregnancies affected (4 CF, 2 FXS, 1 SMA).ConclusionThe combined affected pregnancy rate is comparable to the population risk for Down syndrome, emphasizing the need to routinely offer carrier screening. The availability of appropriate genetic counseling support and a collaborative approach between laboratory teams, genetics services, health professionals offering screening, and support organizations is essential.

Metabolic screening and metabolomics analysis in the Intellectual Developmental Disorders Mexico Study.

OBJECTIVE: Inborn errors of metabolism (IEM) are genetic conditions that are sometimes associated with intellectual developmental disorders (IDD). The aim of this study is to contribute to the metabolic characterization of IDD of unknown etiology in Mexico. MATERIALS AND METHODS: Metabolic screening using tandem mass spectrometry and fluorometry will be performed to rule out IEM. In addition, target metabolomic analysis will be done to characterize the metabolomic profile of patients with IDD. CONCLUSION: Identification of new metabolomic profiles associated with IDD of unknown etiology and comorbidities will contribute to the development of novel diagnostic and therapeutic schemes for the prevention and treatment of IDD in Mexico.

Metabolic screening and metabolomics analysis in the Intellectual Developmental Disorders Mexico Study / Tamiz bioquímico y metabolómico en el estudio de los trastornos del desarrollo intelectual en México

Abstract: Objective: Inborn errors of metabolism (IEM) are genetic conditions that are sometimes associated with intellectual developmental disorders (IDD). The aim of this study is to contribute to the metabolic characterization of IDD of unknown etiology in Mexico. Materials and methods: Metabolic screening using tandem mass spectrometry and fluorometry will be performed to rule out IEM. In addition, target metabolomic analysis will be done to characterize the metabolomic profile of patients with IDD. Conclusion: Identification of new metabolomic profiles associated with IDD of unknown etiology and comorbidities will contribute to the development of novel diagnostic and therapeutic schemes for the prevention and treatment of IDD in Mexico.

Resumen: Objetivo: Los errores innatos del metabolismo (EIM) son condiciones genéticas que pueden asociarse con trastornos del desarrollo intelectual (TDI). El objetivo de este estudio es contribuir a la caracterización metabólica de los pacientes con TDI de etiología desconocida. Material y métodos: Se realizará un tamiz metabólico mediante espectrometría de masas-tándem y fluorometría para descartar EIM; además, se analizará el perfil metabolómico de los pacientes con TDI. Conclusión: La identificación de perfiles metabolómicos asociados con los TDI de etiología desconocida contribuirá al desarrollo de nuevos esquemas diagnósticos y terapéuticos para la prevención y tratamiento de los TDI en México.

Effects of a social stimulus on gene expression in a mouse model of fragile X syndrome.

BACKGROUND: People with fragile X syndrome (FXS) often have deficits in social behavior, and a substantial portion meet criteria for autism spectrum disorder. Though the genetic cause of FXS is known to be due to the silencing of FMR1, and the Fmr1 null mouse model representing this lesion has been extensively studied, the contributions of this gene and its protein product, FMRP, to social behavior are not well understood. METHODS: Fmr1 null mice and wildtype littermates were exposed to a social or non-social stimulus. In one experiment, subjects were assessed for expression of the inducible transcription factor c-Fos in response to the stimulus, to detect brain regions with social-specific activity. In a separate experiment, tissue was taken from those brain regions showing differential activity, and RNA sequencing was performed. RESULTS: Immunohistochemistry revealed a significantly greater number of c-Fos-positive cells in the lateral amygdala and medial amygdala in the brains of mice exposed to a social stimulus, compared to a non-social stimulus. In the prelimbic cortex, there was no significant effect of social stimulus; although the number of c-Fos-positive cells was lower in the social condition compared to the non-social condition, and negatively correlated with c-Fos in the amygdala. RNA sequencing revealed differentially expressed genes enriched for molecules known to interact with FMRP and also for autism-related genes identified in the Simons Foundation Autism Research Initiative gene database. Ingenuity Pathway Analysis detected enrichment of differentially expressed genes in networks and pathways related to neuronal development, intracellular signaling, and inflammatory response. CONCLUSIONS: Using the Fmr1 null mouse model of fragile X syndrome, we have identified brain regions, gene networks, and molecular pathways responsive to a social stimulus. These findings, and future experiments following up on the role of specific gene networks, may shed light on the neural mechanisms underlying dysregulated social behaviors in fragile X syndrome and more broadly.

Informed decision making and psychosocial outcomes in pregnant and nonpregnant women offered population fragile X carrier screening.

PurposePopulation-based carrier screening for fragile X syndrome (FXS) is still not universally endorsed by professional organizations due to concerns around genetic counseling for complex information and potential for psychosocial harms.MethodsWe determined uptake levels, decision making, and psychosocial impact in a prospective study of pregnant and nonpregnant Australian women offered FXS carrier screening in clinical settings. Women received pretest genetic counseling, and completed questionnaires when deciding and one month later.ResultsOf 1,156 women recruited, 83.1% returned the first questionnaire with 70.6% nonpregnant and 58.8% pregnant women choosing testing (χ2=16.98, P<0.001). Overall, informed choice was high in both nonpregnant (77.4%) and pregnant (72.9%) women (χ2=0.21, P=0.644), and more tested (76.0%) than not-tested (66.7%) women (χ2=6.35, P=0.012) made an informed choice. Measures of depression, stress, and anxiety were similar to population norms for ~85% of women. Decisional conflict and regret were generally low; however, decisional uncertainty and regret were greater in pregnant than nonpregnant women, and not-tested than tested women (uncertainty: χ2=18.51, P<0.001 and χ2=43.11, P<0.001, respectively; regret: χ2=6.61, P<0.037 and χ2=35.54, P<0.001, respectively).ConclusionWe provide evidence to inform guidelines that population FXS carrier screening can be implemented with minimal psychosocial harms following appropriate information and prescreening genetic counseling.