Prevalence of the Gene Premutation in Young Women with a Diminished Ovarian Reserve Included in an IVF Program: Implications for Clinical Practice.

The relationship between premature ovarian insufficiency (FXPOI) and premutation in the gene is well established. In recent years, though, a potential relationship between the latter and a low ovarian reserve has been suggested. To explore it, we conducted a retrospective study in an IVF program at a university tertiary referral center in Barcelona (Spain).

Guidelines for NGS procedures applied to prenatal diagnosis by the Spanish Society of Gynecology and Obstetrics and the Spanish Association of Prenatal Diagnosis.

Objective: This document addresses the clinical application of next-generation sequencing (NGS) technologies for prenatal genetic diagnosis and aims to establish clinical practice recommendations in Spain to ensure uniformity in implementing these technologies into prenatal care.

Methods: A joint committee of expert obstetricians and geneticists was created to review the existing literature on fetal NGS for genetic diagnosis and to make recommendations for Spanish healthcare professionals.

Results: This guideline summarises technical aspects of NGS technologies, clinical indications in prenatal setting, considerations regarding findings to be reported, genetic counselling considerations as well as data storage and protection policies.

Enlarged perivascular spaces and their association with motor, cognition, MRI markers and cerebrovascular risk factors in male fragile X premutation carriers.

FMR1 premutation carriers (55-200 CGG repeats) are at risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disorder associated with motor and cognitive impairment. Bilateral hyperintensities of the middle cerebellar peduncles (MCP sign) are the major radiological hallmarks of FXTAS. In the general population, enlarged perivascular spaces (PVS) are biomarkers of small vessel disease and glymphatic dysfunction and are associated with cognitive decline.

Correlation of FMR4 expression levels to ovarian reserve markers in FMR1 premutation carriers.

Background: Fragile X-associated primary ovarian insufficiency (FXPOI), characterized by amenorrhea before age 40 years, occurs in 20% of female FMR1 premutation carriers. Presently, there are no molecular or biomarkers that can help predicting which FMR1 premutation women will develop FXPOI. We previously demonstrated that high FMR4 levels can discriminate between FMR1 premutation carriers with and without FXPOI.

A novel NONO nonsense variant in a fetus with renal abnormalities.

At 16 + 6-weeks a fetal scan performed in the second pregnancy of a 42 y.o. woman identified a right multicystic dysplastic kidney, left renal agenesis, absent urinary bladder, myocardial hypertrophy, increased nuchal fold, a single umbilical artery, and oligohydramnios.

Exploration of SUMO2/3 Expression Levels and Autophagy Process in Fragile X-Associated Tremor/Ataxia Syndrome: Addressing Study Limitations and Insights for Future Research.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that appears in adult premutation carriers. The neuropathological hallmark of FXTAS is an intranuclear inclusion in neurons and astrocytes. Nearly 200 different proteins have been identified in FXTAS inclusions, being the small ubiquitin-related modifier 2 (SUMO2), ubiquitin and p62 the most highly abundant.

Tcf20 deficiency is associated with increased liver fibrogenesis and alterations in mitochondrial metabolism in mice and humans.

Background & Aims: Transcription co-activator factor 20 (TCF20) is a regulator of transcription factors involved in extracellular matrix remodelling. In addition, TCF20 genomic variants in humans have been associated with impaired intellectual disability. Therefore, we hypothesized that TCF20 has several functions beyond those described in neurogenesis, including the regulation of fibrogenesis.

Implementation of Exome Sequencing in Clinical Practice for Neurological Disorders.

Neurological disorders (ND) are diseases that affect the brain and the central and autonomic nervous systems, such as neurodevelopmental disorders, cerebellar ataxias, Parkinson's disease, or epilepsies. Nowadays, recommendations of the American College of Medical Genetics and Genomics strongly recommend applying next generation sequencing (NGS) as a first-line test in patients with these disorders. Whole exome sequencing (WES) is widely regarded as the current technology of choice for diagnosing monogenic ND.

Evaluation of AQP4 functional variants and its association with fragile X-associated tremor/ataxia syndrome.

Introduction: Fragile X-associated tremor/ataxia syndrome (FXTAS, OMIM# 300623) is a late-onset neurodegenerative disorder with reduced penetrance that appears in adult premutation carriers (55-200 CGGs). Clinical symptoms in FXTAS patients usually begin with an action tremor. After that, different findings including ataxia, and more variably, loss of sensation in the distal lower extremities and autonomic dysfunction, may occur, and gradually progress.

Special Issue: Genetics of Psychiatric Disease and the Basics of Neurobiology.

A psychiatric disorder is a mental illness involving significant disturbances in thinking, emotional regulation or behavior [...

Lethal Congenital Contracture Syndrome 11: A Case Report and Literature Review.

Lethal congenital contracture syndrome 11 (LCCS11) is caused by homozygous or compound heterozygous variants in the gene on chromosome 15q21. encodes gliomedin, a protein required for the formation of the nodes of Ranvier and development of the human peripheral nervous system. We report a fetus with ultrasound alterations detected at 28 weeks of gestation.

Bioenergetic and Autophagic Characterization of Skin Fibroblasts from Patients.

The objective of this study is to describe the alterations occurring during the neurodegenerative process in skin fibroblast cultures from patients. We characterized the oxidative stress, autophagy flux, small ubiquitin-related protein SUMO2/3 levels as well as the mitochondrial function in skin fibroblast cultures from patients. All metabolic and bioenergetic findings were further correlated with gene expression data obtained from RNA sequencing analysis.

Evaluation of FMR4, FMR5 and FMR6 Expression Levels as Non-Invasive Biomarkers for the Diagnosis of Fragile X-Associated Primary Ovarian Insufficiency (FXPOI).

Female (Fragile X mental retardation 1) premutation carriers are at risk for developing fragile X-associated primary ovarian insufficiency (FXPOI), a condition characterized by amenorrhea before age 40 years. Not all women with a premutation suffer from primary ovarian insufficiency and nowadays there are no molecular or other biomarkers that can help predict the occurrence of FXPOI. Long non-coding RNAs (lncRNAs) comprise a group of regulatory transcripts which have versatile molecular functions, making them important regulators in all aspects of gene expression.

Diagnostic yield of next-generation sequencing in 87 families with neurodevelopmental disorders.

Background: Neurodevelopmental disorders (NDDs) are a group of heterogeneous conditions, which include mainly intellectual disability, developmental delay (DD) and autism spectrum disorder (ASD), among others. These diseases are highly heterogeneous and both genetic and environmental factors play an important role in many of them. The introduction of next generation sequencing (NGS) has lead to the detection of genetic variants in several genetic diseases.

Reduced mtDNA Copy Number in the Prefrontal Cortex of C9ORF72 Patients.

Hexanucleotide repeat expansion in C9ORF72 gene is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia (C9ALS/FTD). Loss of C9ORF72 protein function and a toxic gain-of-function directly by the RNA or RAN translation have been proposed as triggering pathological mechanisms, along with the accumulation of TDP-43 protein. In addition, mitochondrial defects have been described to be a major driver of disease initiation.

Significance of Low Maternal Serum Β-hCG Levels in the Assessment of the Risk of Atypical Chromosomal Abnormalities.

Introduction: The introduction of prenatal cell-free DNA as a screening test has surpassed traditional combined first-trimester screening (cFTS) in the detection of common trisomies. However, its current limitation in detecting only common trisomies is affecting the diagnostic yield for other clinically significant chromosomal abnormalities.

Methods: In efforts to optimize the detection of fetuses with genetic abnormalities, we have analyzed the relationship between the cFTS risk score and biomarkers with atypical chromosomal abnormalities.

Have maternal or paternal ages any impact on the prenatal incidence of genomic copy number variants associated with fetal structural anomalies?

The objective of this study was to determine whether maternal or paternal ages have any impact on the prenatal incidence of genomic copy number variants (CNV) in fetuses with structural anomalies. We conducted a non-paired case-control study (1:2 ratio) among pregnancies undergoing chromosomal microarray analysis (CMA) because of fetal ultrasound anomalies, from December 2012 to May 2020. Pregnancies with any pathogenic copy number variant (CNV), either microdeletion or microduplication, were defined as cases.

Identifying susceptibility genes for primary ovarian insufficiency on the high-risk genetic background of a fragile X premutation.

Objective: To identify modifying genes that explains the risk of fragile X-associated primary ovarian insufficiency (FXPOI).

Design: Gene-based, case/control association study, followed by a functional screen of highly ranked genes using a Drosophila model.

Setting: Participants were recruited from academic and clinical settings.

Novel Compound Heterozygous Mutation in Gene: The Relevance of Whole Genome Sequencing.

Advances in high-throughput technologies and its implementation worldwide have had a considerable impact on the elucidation of the molecular causes underlying neurodevelopmental psychiatric disorders, especially for autism spectrum disorder and intellectual disability (ID). Nevertheless, etiology remains elusive in close to 50% of cases, even in those families with multiple affected individuals, strongly hinting at a genetic cause. Here we present a case report of two siblings affected with severe ID and other comorbidities, who embarked on a genetic testing odyssey until diagnosis was reached by using whole genome sequencing (WGS).

A New Stepwise Molecular Work-Up After Chorionic Villi Sampling in Women With an Early Pregnancy Loss.

To explore the use of a new molecular work-up based on the stepwise use of Quantitative Fluorescence PCR (QF-PCR) extended to eight chromosomes and single nucleotide polymorphism array (SNP-array) in chorionic villi obtained by chorionic villi sampling (CVS) offered to women experiencing an early pregnancy loss. During a 3-year period (January 2016-December 2018), CVS was offered to women experiencing an early pregnancy loss before the evacuation of the products of conception (POC) to retrieve chorionic villi, irrespective of the number of previous losses. A new molecular work-up was prospectively assayed encompassing a first QF-PCR round (with the 21, 18, 13, 7, X, and Y chromosomes), a second QF-PCR round (with the 15, 16, and 22 chromosomes), and a high resolution SNP-array in those cases with normal QF-PCR results.

Effect of AGG Interruptions on Maternal Transmissions.

There are four classes of CGG repeat alleles in the gene: normal alleles have up to 44 repeats; patients with Fragile X Syndrome have more than 200 repeats; those between 55 and 200 CGGs are considered premutation alleles, because they are associated with maternal expansions of the number of CGGs in the next generation and finally, alleles between 45 and 54 CGGs are called intermediate or gray zone alleles. In these last categories, the stability depends on the presence of AGG interruptions, which usually occurs between 9 and 10 CGGs. In this context, we have studied retrospectively 66 women with CGG repeats between 45 and 65, and their offspring.