Online Cognitive Assessment of 15q11.2 Deletion Carriers Reveals Domain Specific Impairments

Advanced genetic testing has enabled detection of copy number variations (CNVs) which were previously undetectable. The 15q11.2 microdeletion is an example of this sort of CNV. Chromosome 15q11 to q13 is known to be a highly unstable region and therefore associated with high frequency of mutation (Murthy et al, 2007). Specifically, the presence of repeat sequences in low copy numbers at some regions within 15q11 to q13 has created common break point regions including BP1, BP2, and BP3 (Murthy et al, 2007). 15q11.2 microdeletions encompass a lost copy from BP1 to BP2. The four genes in this region are NIPA1, NIPA2, CYFIP1, and TUBGCP5 (De wolf et al, 2013), and the deletion spans from 20,306,549bp to 20,777,695bp on chromosome 15, or approximately about 470 kb (Stefansson et al, 2008). Although 15q11.2 is next to the region associated with Prader-Willi syndrome and Angelman syndrome, it is not overlapping. These two conditions are related specifically to the region between BP2 and BP3. None of the four genes in 15q11.2 region are known to be imprinted, in contrast to some genes in adjacent bands. Deletions in 15q11.2 are known to increase the risk of neurodevelopmental disorders. Specifically, 15q11.2 deletions have been associated with conditions such as developmental delay, autism spectrum disorder, schizophrenia, epilepsy, dyslexia, and dyscalculia (Burnside et al, 2011; Cooper et al, 2011; De Kovel et al, 2010; De wolf et al, 2013; Doornbos et al, 2009; Murthy et al, 2007; Stefansson et al, 2008; Stefansson et al, 2014; Von der Lippe et al, 2010). However, like many other recently detected CNVs, 15q11.2 deletions lack phenotypic specificity. This deletion can manifest with different symptoms in different individuals. To further complicate the matter, 15q11.2 deletions, like many other newly detectable CNVs, are present in the population among those who do not present with any clinically significant symptoms (Stefansson et al, 2014). Therefore, having this deletion creates a susceptibility to some neurodevelopmental disorders, but it is not necessarily causal. Lack of any direct associated phenotype in some carriers of this deletion makes it difficult to predict outcomes. Therefore, it can leave clinicians, such as genetic counselors, challenged to interpret and communicate the meaning of these results to the patients and families (Burnside et al, 2011; Chaste et al, 2014; De wolf et al, 2013). There has been some speculation regarding the possible presence of intermediate phenotypes in 15q11.2 deletion carriers who are not affected (De Wolf et al, 2013, Stefansson et al, 2014). This hypothesis was examined in a paper published in 2014 by Stefansson et al. Stefansson looked for relationships between individuals harboring CNVs known to increase risk for neurodevelopmental disease and altered cognition. The selection of CNVs was based on a literature review to identify those known to be associated with schizophrenia or autism, including 15q11.2 deletions. Subjects were recruited from four groups: carriers of a CNV associated with a neuropsychiatric disorder, including 15q11.2 deletion carriers, carriers of other CNVs not associated with neuropsychiatric disorders, controls with no CNVs, and patients with schizophrenia. Subjects were all between 18 to 65 years old (Stefansson e al, 2014). Participants were tested for cognitive functions including attention, spatial working memory, logical memory, executive functioning, cognitive flexibility, language and speed processing, using standardized tests such as Mini International Neuropsychiatric Interview (M.I.N.I.)(Stefansson et al, 2014). According to Stefansson these cognitive functions are known to be affected in individuals with schizophrenia. In addition, subjects were tested for dyslexia and dyscalculia (Stefansson et al, 2014). In this study, Stefansson found that 15q11.2 deletion carriers’ performance on tests of cognitive function fell between those of general population and patients with schizophrenia. The discrepancy with the general population was greatest for dyslexia and dyscalculia (Stefansson et al, 2014). Stefansson deduced that the cognitive activity of carriers fell somewhere between the non-carriers and patients with schizophrenia, providing support for this hypothesis (Stefansson et al, 2014). In order to further study the effect of CNVs on a carrier’s brain, Stefansson, utilized magnetic resonance imaging (MRI). Carriers of a 15q11.2 deletion were found to have reduced grey matter volume in anterior cingulate cortex and left insula, reduced white matter volume in temporal lobe, and increased corpus callosum volume. Interestingly, the reduced grey matter observed in these carriers is similar to that found in individuals with dyslexia and dyscalculia. Stefansson concluded that perhaps 15q11.2 events are associated with specific aspects of cognition and brain structure (Stefansson et al, 2014). Prior to Stefansson’s work, Murthy et al, in 2007, published the first case report on a three and a half year old boy with a 253 Kb deletion in 15q11.2, between bp1 and bp2. Prior to this report, other reported cases of 15q11.2 deletions were larger and not limited to the region between bp1 and bp2 (Butler 2004, and Milner 2005). Those cases had deletions that included the region between BP2 and BP3, and hence usually a diagnosis of Prader-Willi syndrome or Angelman syndrome. Murthy reported on a patient with mental retardation, developmental delay and speech problems. The deletion was found to be paternally inherited. The child’s father had similar but milder symptoms (Murthy et al, 2007). However, Murthy did not speculate any reason for the milder presentation in the father. Doornbos et al, published the second case report, reporting on 9 cases in 2009. Probands all harbored 15q11.2 deletions and manifested developmental delay, mental retardation, dysmorphic facial features and behavioral problems. Behavioral problems encompassed autism, attention deficit hyperactivity disorder (ADHD), and obsessivecompulsive disorder (OCD). A control population of 350 was screened, and no deletion carriers were found. This group concluded that there might be a correlation between 15q11.2 deletions and developmental delay and mental retardation. In this study, 7 of the 9 reported patients were noted to have inherited the deletion from an unaffected or a mildly affected parent (Doornbos et al, 2009). Again, no rationale for the milder presentation of these individuals was offered. In 2010, Von der Lippe et al, reported on 7 patients with the same symptoms as those described by Doornbos patients, except facial dysmorphism. This study provided additional support for the association of developmental delay, mental retardation and behavioral problems with 15q11.2 deletions (Von der Lippe et al, 2010). The first large study of 15q11.2 deletions was done in 2008, a year after the first case report. Investigators were interested to know whether there was an association between schizophrenia and three recently discovered common deletions, including 15q11.2. They screened a population of 4,718 patients with schizophrenia for the three deletions, and compared it to the prevalence of the deletion in a control population of 41,194. With regards to 15q11.2 deletions, 26 of 4,718 (0.55%) patients with schizophrenia and psychosis were carriers while only 79 of 41,194 (0.19%) controls had the deletion (Stefansson et al, 2008). This group concluded that indeed there was an association between schizophrenia and 15q11.2 deletions. In 2012, Van Den Bossche et al, confirmed this association by screening a different population of patients with schizophrenia as well as patients with bipolar disorder, major depressive disorder, and intellectual disability, for deletions in 15q11.2. 15q11.2 deletions were found to be associated with increased susceptibility to both schizophrenia and intellectual disability. This group speculated that CNVs in this region could cause disturbances in brain development, which consequently can increase predisposition to different neuropsychiatric conditions (Van Den Bossche et al, 2012). In 2010, De Kovel et al looked at the association of five commonly reported deletions, including 15q11.2 deletions, with epilepsy. This study looked at the prevalence of these deletions in a patient population with common idiopathic generalized epilepsy syndrome, and 12 of 1234 (1%) patients and 6 of 3022 (0.2%) controls were found to have 15q112 microdeletions (Kovel et al, 2010). Therefore, this group concluded a susceptibility to epilepsy did exist for carriers of this deletion. All these cases were inherited from a non-affected parent, and again no explanation for this finding was offered. In 2011, Cooper et al, screened a large sample of 15,767 children with intellectual disability and developmental delay for the presence of 15q11.2 deletion, and compared it to 8329 unaffected adults patients. This group found the 15q11.2 deletion in one out of every 167 affected patients with intellectual disability and developmental delay, providing support for the association of 15q11.2 deletion with intellectual disability and developmental delay (Cooper et al, 2011). Additionally, Burnside et al, in the same year, screened a total of 3,992 patients. Patients were affected with autism, developmental delay, motor and language delays, and behavioral problems. A total of 0.86% of the 3,992 were found to carry either duplication or a deletion (0.41% deletion) in the 15q11.2 region. However, only 0.38% of 6,329 controls were found to carry a mutation in 15q11.2 (Burnside et al, 2011). Most of the mutations in Burnside study were inherited from unaffected parents. Possible explanations for these results included “reduced penetrance, altered gene dosage on a particular genetic background, or a susceptibility region as reported for other areas of the genome implicated in autism and behavior disturbances” (Burnside, 2011). The current study assessed the cognitive phenotypes of 15q11.2 deletion carriers. As demonstrated above, unaffected parents harboring a 15q11.2 deletion were observed in most of the studies. Finding a possible intermediate or associated phenotype in the 15q11.2 deletion carriers would not only provide important insight into this deletion’s neurobiology, but also aid clinicians to interpret the outcome of such deletions for patients with increased certainty

Association between anogenital distance as a noninvasive index in the diagnosis and prognosis of reproductive disorder: A systematic review

Background: There are 2 measures of anogenital distance (AGD) in men and women. AGD has been used as an indicator of fetal androgen dysfunction and an adverse outcome in adulthood. Some studies have shown the association of AGD as a predictor in the diagnosis and prognosis of diseases and disorders. Objective: To systematically summarize the latest evidence for presenting AGD as a new approach for prognosis and early diagnosis of diseases. Materials and Methods: A systematic review of the available literature was performed using Medline via PubMed, Scopus, and ISI Web of Knowledge up to July 2021, using search terms “anogenital distance” OR “anogenital index” OR “ano genital distance” OR “ano genital index”. Language restrictions were not imposed. Results: After reviewing the retrieved articles, 47 unique studies were included in this systematic review. Different outcomes, including endometriosis, prostate cancer, polycystic ovary syndrome, pelvic organ prolapse, hypospadias, cryptorchidism, fertility and semen parameters, maternal and birth development, and ovarian and gynecological-related disorders, have been studied in the included evidence. A negative association was observed between AGD and endometriosis and hypospadias and a positive association between AGD and prostate cancer, polycystic ovary syndrome, male fetal gender, and fertility parameters. Conclusion: Using quantitative indicators such as AGD may be a useful clinical tool for diagnosing diseases. Although many studies have shown an association between AGD and diseases, some factors, including different measurement methods, different measurement tools, age, and different definitions of AGD, can be involved in the variation of AGD. Key words: Genitalia, Prognosis, Early diagnosis, Reproductive health

Comparison of Cone Beam Computed Tomography and Digital Radiography in Detecting Separated Endodontic Files and Strip Perforation

The separation of endodontic files and strip perforation are among procedural intraoperative complications which may ultimately lead to the failure of root canal treatment. The aim of the present study was to compare the diagnostic potential of cone beam computed tomography (CBCT) and digital periapical radiographs in detecting separated rotary files and strip perforation in filled canals. Fifty human mandibular molars were selected for this study. The teeth were randomly divided into two groups based on endodontic errors (i.e., file separation and strip perforation). In each group, 25 of 50 mesial canals were randomly chosen for simulating the errors, while the other 25 canals were considered as the control group. In group one, a simulation of the separation of rotary files was performed using ProTaper F2 files. Strip perforation of the root canals in group two was achieved by number 2 and 3 Gates Glidden drills in the coronal third of the root canals. Digital periapical radiographs in two different horizontal angles and high-resolution CBCT scans were obtained from the teeth mounted on a dry human mandible with simulated soft tissue covering. Three experienced observers who were unaware of the study groups evaluated the digital periapical and CBCT image sets in two separate readings. Intraobserver and interobserver agreements, as well as accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were calculated and compared. Intraobserver and interobserver agreements ranged from poor to excellent and poor to good, respectively. The accuracy, sensitivity, specificity, PPV, and NPV for digital radiography in detecting separated files were 0.950, 0.813, 0.957, 0.929, and 0.880, respectively. The same values for CBCT were 0.747, 0.667, 0.900, 0.833, and 0.783, respectively. For the diagnosis of strip perforation, these values were 0.855, 0.800, 0.909, 0.889, and 0.833 for periapical radiography and 0.955, 1.000, 0.920, 0.926, and 1.000 for CBCT. In conclusion, CBCT was superior for diagnosing strip perforation of the filled root canals, while digital periapical radiographs performed better in the detection of separated rotary files

HB5 aptamer-tagged graphene oxide for co-delivery of doxorubicin and silibinin, and highly effective combination therapy in breast cancer

Abstract Using a chemotherapeutic agent, such as doxorubicin (DOX), with a natural agent, such as silibinin (Sili), is highly valuable to minimize systemic toxicity. However, Sili and DOX face disadvantages, such as low aqueous solubility and poor bioavailability. Here, we have engineered a drug delivery cargo by decorating carboxylated graphene oxide (cGO) with an aptamer, HB5, for simultaneous delivery of DOX and Sili as a combination therapy against MCF-7 and SK-BR-3 breast cancer cells. The resulting Apt-cGO displayed a typical sheet-like nanostructure with a broad surface. The maximum entrapment efficiency was 70.42% and 84.22% for Sili and DOX, respectively. When the Apt-cGO-DOX-Sili nanocomposites were selectively taken up by breast cancer cells, the interaction between cGO and drugs was cleaved, causing releasing both Sili and DOX into the tumor cells, respectively. Compared to free drugs, Apt-cGO-DOX-Sili nanocomposites displayed higher cytotoxicity in vitro. Apt-cGO-DOX-Sili nanocomposites potentially suppressed some cancer cell survival signals. They accelerated cell apoptosis and increased Rb levels as well as reduced Akt, mTOR, NF-κB, and CDK2 levels. In conclusion, the developed Apt-cGO-DOX-Sili can be suggested as a simple and efficient drug delivery approach for breast chemotherapy

Loss-of-function variants in NFIA provide further support that NFIA is a critical gene in 1p32-p31 deletion syndrome: A four patient series

International audienceFrontonasal dysplasias are rare congenital malformations of frontonasal process-derived structures, characterized by median cleft, nasal anomalies, widely spaced eyes, and cranium bifidum occultum. Several entities of syndromic frontonasal dysplasia have been described, among which, to date, only a few have identified molecular bases. We clinically ascertained a cohort of 124 individuals referred for frontonasal dysplasia. We identified six individuals with a similar phenotype, including one discordant monozygous twin. Facial features were remarkable by nasal deformity with creased ridge and depressed or absent tip, widely spaced eyes, almond-shaped palpebral fissures, and downturned corners of the mouth. All had apparently normal psychomotor development. In addition, upper limb anomalies, frontonasal encephalocele, corpus callosum agenesis, choanal atresia, and congenital heart defect were observed. We identified five reports in the literature of patients presenting with the same phenotype. Exome sequencing was performed on DNA extracted from blood of two individuals, no candidate gene was identified. In conclusion, we report six novel simplex individuals presenting with a specific frontonasal dysplasia entity associating recognizable facial features, limb and visceral malformations, and apparently normal development. The identification of discordant monozygotic twins supports the hypothesis of a mosaic disorder. Although previous patients have been reported, this is the first series, allowing delineation of a clinical subtype of frontonasal dysplasia, paving the way toward the identification of its molecular etiology

Germline de novo mutations in GNB1 cause severe neurodevelopmental disability, hypotonia, and seizures

Whole-exome sequencing of 13 individuals with developmental delay commonly accompanied by abnormal muscle tone and seizures identified de novo missense mutations enriched within a sub-region of GNB1, a gene encoding the guanine nucleotide-binding protein subunit beta-1, Gβ. These 13 individuals were identified among a base of 5,855 individuals recruited for various undiagnosed genetic disorders. The probability of observing 13 or more de novo mutations by chance among 5,855 individuals is very low (p = 7.1 × 10), implicating GNB1 as a genome-wide-significant disease-associated gene. The majority of these 13 mutations affect known Gβ binding sites, which suggests that a likely disease mechanism is through the disruption of the protein interface required for Gα-Gβγ interaction (resulting in a constitutively active Gβγ) or through the disruption of residues relevant for interaction between Gβγ and certain downstream effectors (resulting in reduced interaction with the effectors). Strikingly, 8 of the 13 individuals recruited here for a neurodevelopmental disorder have a germline de novo GNB1 mutation that overlaps a set of five recurrent somatic tumor mutations for which recent functional studies demonstrated a gain-of-function effect due to constitutive activation of G protein downstream signaling cascades for some of the affected residues

De novo mutations in the GTP/GDP-binding region of RALA, a RAS-like small GTPase, cause intellectual disability and developmental delay.

Mutations that alter signaling of RAS/MAPK-family proteins give rise to a group of Mendelian diseases known as RASopathies. However, among RASopathies, the matrix of genotype-phenotype relationships is still incomplete, in part because there are many RAS-related proteins and in part because the phenotypic consequences may be variable and/or pleiotropic. Here, we describe a cohort of ten cases, drawn from six clinical sites and over 16,000 sequenced probands, with de novo protein-altering variation in RALA, a RAS-like small GTPase. All probands present with speech and motor delays, and most have intellectual disability, low weight, short stature, and facial dysmorphism. The observed rate of de novo RALA variants in affected probands is significantly higher (p = 4.93 x 10(-11)) than expected from the estimated random mutation rate. Further, all de novo variants described here affect residues within the GTP/GDP-binding region of RALA; in fact, six alleles arose at only two codons, Val25 and Lys128. The affected residues are highly conserved across both RAL- and RAS-family genes, are devoid of variation in large human population datasets, and several are homologous to positions at which disease-associated variants have been observed in other GTPase genes. We directly assayed GTP hydrolysis and RALA effector-protein binding of the observed variants, and found that all but one tested variant significantly reduced both activities compared to wild-type. The one exception, S157A, reduced GTP hydrolysis but significantly increased RALA-effector binding, an observation similar to that seen for oncogenic RAS variants. These results show the power of data sharing for the interpretation and analysis of rare variation, expand the spectrum of molecular causes of developmental disability to include RALA, and provide additional insight into the pathogenesis of human disease caused by mutations in small GTPases

The Epilepsy Genetics Initiative: Systematic reanalysis of diagnostic exomes increases yield

Objective: The Epilepsy Genetics Initiative (EGI) was formed in 2014 to create a centrally managed database of clinically generated exome sequence data. EGI performs systematic research-based reanalysis to identify new molecular diagnoses that were not possible at the time of initial sequencing and to aid in novel gene discovery. Herein we report on the efficacy of this approach 3 years after inception.Methods: One hundred sixty-six individuals with epilepsy who underwent diagnostic whole exome sequencing (WES) were enrolled, including 139 who had not received a genetic diagnosis. Sequence data were transferred to the EGI and periodically reevaluated on a research basis.Results: Eight new diagnoses were made as a result of updated annotations or the discovery of novel epilepsy genes after the initial diagnostic analysis was performed. In five additional cases, we provided new evidence to support or contradict the likelihood of variant pathogenicity reported by the laboratory. One novel epilepsy gene was discovered through dual interrogation of research and clinically generated WES.Significance: EGI's diagnosis rate of 5.8% represents a considerable increase in diagnostic yield and demonstrates the value of periodic reinterrogation of whole exome data. The initiative's contributions to gene discovery underscore the importance of data sharing and the value of collaborative enterprises.</p