Premature primary tooth eruption in cognitive/motor-delayed ADNP-mutated children

Extended phenotypic characterization of a novel Helsmoortel-van der Aa syndrome case series

The neurodevelopmental disorder known as Helsmoortel-van der Aa syndrome (HVDAS, MIM#616580) or ADNP syndrome (Orphanet, ORPHA:404448) is a multiple congenital anomaly (MCA) condition, reported as a syndrome in 2014, associated with deleterious variants in the ADNP gene (activity-dependent neuroprotective protein; MIM*611386) in several children. First reported in the turn of the century, ADNP is a protein with crucial functions for the normal development of the central nervous system and with pleiotropic effects, explaining the multisystemic character of the syndrome. Affected individuals present with striking facial dysmorphic features and variable congenital defects. Herein, we describe a novel case series of HVDAS Italian patients, illustrating their clinical findings and the related genotype-phenotype correlations. Interestingly, the cutaneous manifestations are also extensively expanded, giving an important contribution to the clinical characterization of the condition, and highlighting the relation between skin abnormalities and ADNP defects.

ADNP dysregulates methylation and mitochondrial gene expression in the cerebellum of a Helsmoortel-Van der Aa syndrome autopsy case

BACKGROUND

Helsmoortel-Van der Aa syndrome is a neurodevelopmental disorder in which patients present with autism, intellectual disability, and frequent extra-neurological features such as feeding and gastrointestinal problems, visual impairments, and cardiac abnormalities. All patients exhibit heterozygous de novo nonsense or frameshift stop mutations in the Activity-Dependent Neuroprotective Protein (ADNP) gene, accounting for a prevalence of 0.2% of all autism cases worldwide. ADNP fulfills an essential chromatin remodeling function during brain development. In this study, we investigated the cerebellum of a died 6-year-old male patient with the c.1676dupA/p.His559Glnfs*3 ADNP mutation.

RESULTS

The clinical presentation of the patient was representative of the Helsmoortel-Van der Aa syndrome. During his lifespan, he underwent two liver transplantations after which the child died because of multiple organ failure. An autopsy was performed, and various tissue samples were taken for further analysis. We performed a molecular characterization of the cerebellum, a brain region involved in motor coordination, known for its highest ADNP expression and compared it to an age-matched control subject. Importantly, epigenome-wide analysis of the ADNP cerebellum identified CpG methylation differences and expression of multiple pathways causing neurodevelopmental delay. Interestingly, transcription factor motif enrichment analysis of differentially methylated genes showed that the ADNP binding motif was the most significantly enriched. RNA sequencing of the autopsy brain further identified downregulation of the WNT signaling pathway and autophagy defects as possible causes of neurodevelopmental delay. Ultimately, label-free quantification mass spectrometry identified differentially expressed proteins involved in mitochondrial stress and sirtuin signaling pathways amongst others. Protein-protein interaction analysis further revealed a network including chromatin remodelers (ADNP, SMARCC2, HDAC2 and YY1), autophagy-related proteins (LAMP1, BECN1 and LC3) as well as a key histone deacetylating enzyme SIRT1, involved in mitochondrial energy metabolism. The protein interaction of ADNP with SIRT1 was further biochemically validated through the microtubule-end binding proteins EB1/EB3 by direct co-immunoprecipitation in mouse cerebellum, suggesting important mito-epigenetic crosstalk between chromatin remodeling and mitochondrial energy metabolism linked to autophagy stress responses. This is further supported by mitochondrial activity assays and stainings in patient-derived fibroblasts which suggest mitochondrial dysfunctions in the ADNP deficient human brain.

CONCLUSION

This study forms the baseline clinical and molecular characterization of an ADNP autopsy cerebellum, providing novel insights in the disease mechanisms of the Helsmoortel-Van der Aa syndrome. By combining multi-omic and biochemical approaches, we identified a novel SIRT1-EB1/EB3-ADNP protein complex which may contribute to autophagic flux alterations and impaired mitochondrial metabolism in the Helsmoortel-Van der Aa syndrome and holds promise as a new therapeutic target.

Caregiver-reported dental manifestations in individuals with genetic neurodevelopmental disorders

BACKGROUND

Children with neurodevelopmental disorders (NDDs) often have poor oral health and dental abnormalities. An increasing number of genes have been associated with neurodevelopmental conditions affecting the oral cavity, but the specific dental features associated with many genes remain unknown.

AIM

To report the types and frequencies of dental manifestations in children with neurodevelopmental conditions of known genetic cause.

DESIGN

A 30-question survey assesing ectodermal and dental features was administered through Simons Searchlight, with which formed a recontactable cohort of individuals with genetic NDDs often associated with autism spectrum disorder (ASD).

RESULTS

Data were collected from a largely paediatric population with 620 affected individuals across 39 genetic conditions and 145 unaffected siblings without NDDs for comparison. Drooling, difficulty accessing dental care, late primary teeth eruption, abnormal primary and permanent teeth formation, misshapen nails, and hair loss were more frequent in individuals with NDDs. Additionally, we evidenced an association between three new pathogenic gene variant/oral manifestation pairs: CSNK2A1/unusual primary teeth, DYRK1A/late primary teeth eruption, and PPP2R5D/sialorrhea.

CONCLUSION

Our results demonstrate that genetic NDDs caused by mutations in CSNK2A1, DYRK1A, and PP2R5D are associated with unique dental manifestations, and knowledge of these features can be helpful to personalize dental care.

Loss-of-function of activity-dependent neuroprotective protein (ADNP) by a splice-acceptor site mutation causes Helsmoortel-Van der Aa syndrome

Mutations in ADNP result in Helsmoortel-Van der Aa syndrome. Here, we describe the first de novo intronic deletion, affecting the splice-acceptor site of the first coding ADNP exon in a five-year-old girl with developmental delay and autism. Whereas exome sequencing failed to detect the non-coding deletion, genome-wide CpG methylation analysis revealed an episignature suggestive of a Helsmoortel-Van der Aa syndrome diagnosis. This diagnosis was further supported by PhenoScore, a novel facial recognition software package. Subsequent whole-genome sequencing resolved the three-base pair ADNP deletion c.[-5-1_-4del] with transcriptome sequencing showing this deletion leads to skipping of exon 4. An N-terminal truncated protein could not be detected in transfection experiments with a mutant expression vector in HEK293T cells, strongly suggesting this is a first confirmed diagnosis exclusively due to haploinsufficiency of the ADNP gene. Pathway analysis of the methylome indicated differentially methylated genes involved in brain development, the cytoskeleton, locomotion, behavior, and muscle development. Along the same line, transcriptome analysis identified most of the differentially expressed genes as upregulated, in line with the hypomethylated CpG episignature and confirmed the involvement of the cytoskeleton and muscle development pathways that are also affected in patient cell lines and animal models. In conclusion, this novel mutation for the first time demonstrates that Helsmoortel-Van der Aa syndrome can be caused by a loss-of-function mutation. Moreover, our study elegantly illustrates the use of EpiSignatures, WGS and Phenoscore as novel complementary diagnostic tools in case a of negative WES result.

Transient peripheral blood transcriptomic response to ketamine treatment in children with ADNP syndrome

Activity-dependent neuroprotective protein (ADNP) syndrome is a rare neurodevelopmental disorder resulting in intellectual disability, developmental delay and autism spectrum disorder (ASD) and is due to mutations in the ADNP gene. Ketamine treatment has emerged as a promising therapeutic option for ADNP syndrome, showing safety and apparent behavioral improvements in a first open label study. However, the molecular perturbations induced by ketamine remain poorly understood. Here, we investigated the longitudinal effect of ketamine on the blood transcriptome of 10 individuals with ADNP syndrome. Transcriptomic profiling was performed before and at multiple time points after a single low-dose intravenous ketamine infusion (0.5mg/kg). We show that ketamine triggers immediate and profound gene expression alterations, with specific enrichment of monocyte-related expression patterns. These acute alterations encompass diverse signaling pathways and co-expression networks, implicating up-regulation of immune and inflammatory-related processes and down-regulation of RNA processing mechanisms and metabolism. Notably, these changes exhibit a transient nature, returning to baseline levels 24 hours to 1 week after treatment. These findings enhance our understanding of ketamine's molecular effects and lay the groundwork for further research elucidating its specific cellular and molecular targets. Moreover, they contribute to the development of therapeutic strategies for ADNP syndrome and potentially, ASD more broadly.

Longitudinal Genotype-Phenotype (Vineland Questionnaire) Characterization of 15 ADNP Syndrome Cases Highlights Mutated Protein Length and Structural Characteristics Correlation with Communicative Abilities Accentuated in Males

Activity-dependent neuroprotective protein (ADNP) is essential for neurodevelopment and de novo mutations in ADNP cause the ADNP syndrome. From brain pathologies point of view, tauopathy has been demonstrated at a young age, implying stunted development coupled with early/accelerated neurodegeneration. Given potential genotype-phenotype differences and age-dependency, we have assessed here a cohort of 15 individuals (1-27-year-old), using 1-3 longitudinal parent (caretaker) interview/s (Vineland 3 questionnaire) over several years. Our results indicated developmental delays, or even developmental arrests, coupled with potential spurts of development at early ages. Severe outcomes correlated with the truncating high impact mutation, in other words, the remaining mutated protein length as well as with the tested individual age, corroborating the hypothesis of developmental delays coupled with accelerated aging. A significant correlation was noted between mutated protein length and communication, implying a high impact of ADNP on communicative skills. Additionally, correlations were discovered between the two previously described epi-genetic signatures in ADNP emphasizing aberrant acquisition of motor behaviors, with truncating mutations around the nuclear localization signal being mostly affected. Finally, all individuals seem to acquire an age equivalent of 1-6 years, requiring disease modification treatment, such as the ADNP-derived drug candidate, NAP (davunetide), which has recently shown efficacy in women suffering from the neurodegenerative disorder, progressive supranuclear palsy (PSP), a late-onset tauopathy.

Tau, ADNP, and sex

With 50 years to the original discovery of Tau, I gave here my perspective, looking through the prism of activity-dependent neuroprotective protein (ADNP), and the influence of sex. My starting point was vasoactive intestinal peptide (VIP), a regulator of ADNP. I then moved to the original discovery of ADNP and its active neuroprotective site, NAP, drug candidate, davunetide. Tau-ADNP-NAP interactions were then explained with emphasis on sex and future translational medicine.

Microtubule stabilising peptides: new paradigm towards management of neuronal disorders

Neuronal cells made of soma, axon, and dendrites are highly compartmentalized and possess a specialized transport system that can convey long-distance electrical signals for the cross-talk. The transport system is made up of microtubule (MT) polymers and MT-binding proteins. MTs play vital and diverse roles in various cellular processes. Therefore, defects and dysregulation of MTs and their binding proteins lead to many neurological disorders as exemplified by Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, and many others. MT-stabilising agents (MSAs) altering the MT-associated protein connections have shown great potential for several neurodegenerative disorders. Peptides are an important class of molecules with high specificity, biocompatibility and are devoid of side effects. In the past, peptides have been explored in various neuronal disorders as therapeutics. Davunetide, a MT-stabilising octapeptide, has entered into phase II clinical trials for schizophrenia. Numerous examples of peptides emerging as MSAs reflect the emergence of a new paradigm for peptides which can be explored further as drug candidates for neuronal disorders. Although small molecule-based MSAs have been reviewed in the past, there is no systematic review in recent years focusing on peptides as MSAs apart from davunetide in 2013. Therefore, a systematic updated review on MT stabilising peptides may shed light on many hidden aspects and enable researchers to develop new therapies for diseases related to the CNS. In this review we have summarised the recent examples of peptides as MSAs.

NAP (Davunetide): The Neuroprotective ADNP Drug Candidate Penetrates Cell Nuclei Explaining Pleiotropic Mechanisms

(1) Background: Recently, we showed aberrant nuclear/cytoplasmic boundaries/activity-dependent neuroprotective protein (ADNP) distribution in ADNP-mutated cells. This malformation was corrected upon neuronal differentiation by the ADNP-derived fragment drug candidate NAP (davunetide). Here, we investigated the mechanism of NAP nuclear protection. (2) Methods: CRISPR/Cas9 DNA-editing established N1E-115 neuroblastoma cell lines that express two different green fluorescent proteins (GFPs)-labeled mutated ADNP variants (p.Tyr718* and p.Ser403*). Cells were exposed to NAP conjugated to Cy5, followed by live imaging. Cells were further characterized using quantitative morphology/immunocytochemistry/RNA and protein quantifications. (3) Results: NAP rapidly distributed in the cytoplasm and was also seen in the nucleus. Furthermore, reduced microtubule content was observed in the ADNP-mutated cell lines. In parallel, disrupting microtubules by zinc or nocodazole intoxication mimicked ADNP mutation phenotypes and resulted in aberrant nuclear-cytoplasmic boundaries, which were rapidly corrected by NAP treatment. No NAP effects were noted on ADNP levels. Ketamine, used as a control, was ineffective, but both NAP and ketamine exhibited direct interactions with ADNP, as observed via in silico docking. (4) Conclusions: Through a microtubule-linked mechanism, NAP rapidly localized to the cytoplasmic and nuclear compartments, ameliorating mutated ADNP-related deficiencies. These novel findings explain previously published gene expression results and broaden NAP (davunetide) utilization in research and clinical development.

Characterizing Sensory Phenotypes of Subgroups with a Known Genetic Etiology Pertaining to Diagnoses of Autism Spectrum Disorder and Intellectual Disability

We aimed to identify unique constellations of sensory phenotypes for genetic etiologies associated with diagnoses of autism spectrum disorder (ASD) and intellectual disability (ID). Caregivers reported on sensory behaviors via the Sensory Profile for 290 participants (younger than 25 years of age) with ASD and/or ID diagnoses, of which ~ 70% have a known pathogenic genetic etiology. Caregivers endorsed poor registration (i.e., high sensory threshold, passive behaviors) for all genetic subgroups relative to an "idiopathic" comparison group with an ASD diagnosis and without a known genetic etiology. Genetic profiles indicated prominent sensory seeking in ADNP, CHD8, and DYRK1A, prominent sensory sensitivities in SCN2A, and fewer sensation avoidance behaviors in GRIN2B (relative to the idiopathic ASD comparison group).

Chromatin remodeler Activity-Dependent Neuroprotective Protein (ADNP) contributes to syndromic autism

BACKGROUND

Individuals affected with autism often suffer additional co-morbidities such as intellectual disability. The genes contributing to autism cluster on a relatively limited number of cellular pathways, including chromatin remodeling. However, limited information is available on how mutations in single genes can result in such pleiotropic clinical features in affected individuals. In this review, we summarize available information on one of the most frequently mutated genes in syndromic autism the Activity-Dependent Neuroprotective Protein (ADNP).

RESULTS

Heterozygous and predicted loss-of-function ADNP mutations in individuals inevitably result in the clinical presentation with the Helsmoortel-Van der Aa syndrome, a frequent form of syndromic autism. ADNP, a zinc finger DNA-binding protein has a role in chromatin remodeling: The protein is associated with the pericentromeric protein HP1, the SWI/SNF core complex protein BRG1, and other members of this chromatin remodeling complex and, in murine stem cells, with the chromodomain helicase CHD4 in a ChAHP complex. ADNP has recently been shown to possess R-loop processing activity. In addition, many additional functions, for instance, in association with cytoskeletal proteins have been linked to ADNP.

CONCLUSIONS

We here present an integrated evaluation of all current aspects of gene function and evaluate how abnormalities in chromatin remodeling might relate to the pleiotropic clinical presentation in individual"s" with Helsmoortel-Van der Aa syndrome.

ADNP Syndrome: A Qualitative Assessment of Symptoms, Therapies, and Challenges

ADNP syndrome is a neurodevelopmental disorder characterized by autism spectrum disorder (ASD), intellectual disability, sensory reactivity symptoms, facial dysmorphisms, and a wide variety of other physical and behavioral health manifestations. Research on ADNP syndrome has been limited, and there are currently no validated tools for assessing clinical outcomes in ADNP syndrome specifically. The goal of this qualitative study was to ascertain the symptoms of ADNP syndrome based on caregiver interviews, with the primary aim of identifying areas for clinical improvement that may inform the development of outcome measures specific to ADNP syndrome. Data collection consisted of loosely structured interviews with 10 caregivers of children with ADNP syndrome, representing 6 males and 4 females of ages 4 to 17 (M = 10.1; SD = 4.2). Interviews were conducted via phone between November 2020 and April 2021. The analysis of coded interview data identified three overarching themes: symptoms, therapies, and challenges. Each theme encompasses several distinct codes, which were individually addressed. Our results could ultimately be useful in educating clinicians about ADNP syndrome, selecting or designing refined outcome measures for clinical trials, and informing efforts to increase support for caregivers.

A novel davunetide (NAPVSIPQQ to NAPVSIPQE) point mutation in activity-dependent neuroprotective protein (ADNP) causes a mild developmental syndrome

NAP (NAPVSIPQ, drug candidate name, davunetide) is the neuroprotective fragment of activity-dependent neuroprotective protein (ADNP). Recent studies identified NAPVSIP as a Src homology 3 (SH3) domain-ligand association site, responsible for controlling signalling pathways regulating the cytoskeleton. Furthermore, the SIP motif in NAP/ADNP was identified as crucial for direct microtubule end-binding protein interaction facilitating microtubule dynamics and Tau microtubule interaction, at the microtubule end-binding protein site EB1 and EB3. Most de novo ADNP mutations reveal heterozygous STOP or frameshift STOP aberrations, driving the autistic/intellectual disability-related ADNP syndrome. Here, we report for the first time on a de novo missense mutation, resulting in ADNP containing NAPVISPQE instead of NAPVSIPQQ, in a child presenting developmental hypotonia, possibly associated with inflammation affecting food intake in early life coupled with fear of peer interactions and suggestive of a novel case of the ADNP syndrome. In silico modelling showed that the mutation Q (polar side chain) to E (negative side chain) affected the electrostatic characteristics of ADNP (reducing, while scattering the electrostatic positive patch). Comparison with the most prevalent pathogenic ADNP mutation, p.Tyr719*, indicated a further reduction in the electrostatic patch. Previously, exogenous NAP partially ameliorated deficits associated with ADNP p.Tyr719* mutations in transfected cells and in CRISPR/Cas9 genome edited cell and mouse models. These findings stress the importance of the NAP sequence in ADNP and as a future putative therapy for the ADNP syndrome.

Helsmoortel-van der Aa syndrome in a Chinese pediatric patient due to ADNP nonsense mutation: A case report

Background

Helsmoortel-van der Aa syndrome, also known as ADNP syndrome, is a condition that causes developmental delay, language impairment, autism spectrum, and variable extraneurologic features. It is caused by heterozygous mutations in the ADNP gene on chromosome 20q13. Most of the genetic causes of Helsmoortel-van der Aa syndrome have been reported are as de novo nonsense or frameshift stop mutations in exon 5 of ADNP gene, while fewer truncating variants were discovered in exons 4 and the 5' end of exon 5.

Methods

In our study, a 4-year-old female Chinese patient was reported with delayed psychomotor development, language impairment, ataxia, anxiety, aggressive behavior, and congenital heart defect. Trio whole exome sequencing and copy number variation sequencing were performed.

Results

A novel de novo heterozygous pathogenic mutation c.568C > T (p.Gln190Ter) was identified in the ADNP gene of the proband. His unaffected parents did not have the variant. According to the American College of Medical Genetics (ACMG) guidelines, c.568C > T was classified as "pathogenic".

Conclusion

Our report indicated that c.568C > T (p.Gln190Ter) in ADNP gene is the cause of abnormal development of the nervous system, congenital heart disease and strabismus, broadening the spectrum of ADNP gene mutations associated with Helsmoortel-van der Aa syndrome.

Expanding the spectrum of ADNP-related disorder-Antenatally diagnosed congenital diaphragmatic hernia and a novel de novo mutation in ADNP gene

De novo heterozygous ADNP variants have been associated with a complex neurological phenotype characterized primarily by neurodevelopmental delay. Cardiac and renal anomalies have additionally been observed in a few patients. All reported cases to date have been ascertained postnatally. Congenital diaphragmatic hernia (CDH) has been previously observed in one child diagnosed with a de novo ADNP-related neurodevelopmental disorder. We report a fetus who presented with syndromic CDH associated with a de novo heterozygous ADNP variant.

Helsmoortel-Van der Aa Syndrome-Cardiothoracic and Ectodermal Manifestations in Two Patients as Further Support of a Previous Observation on Phenotypic Overlap with RASopathies

The ADNP-gene-related neurodevelopmental disorder Helsmoortel-Van der Aa syndrome is a rare syndromic-intellectual disability-an autism spectrum disorder first described by Helsmoortel and Van der Aa in 2014. Recently, a large cohort including 78 patients and their detailed phenotypes were presented by Van Dijck et al., 2019, who reported developmental delay, speech delay and autism spectrum disorder as nearly constant findings with or without variable cardiological, gastroenterological, urogenital, endocrine and neurological manifestations. Among cardiac malformations, atrial septal defect, patent ductus arteriosus, patent foramen ovale and mitral valve prolapse were the most common findings, but other unspecified defects, such as mild pulmonary valve stenosis, were also described. We present two patients with pathogenic ADNP variants and unusual cardiothoracic manifestations-Bland-White-Garland syndrome, pectus carinatum superiorly along the costochondral junctions and pectus excavatum inferiorly in one patient, and Kawasaki syndrome with pericardiac effusion, coronary artery dilatation and aneurysm in the other-who were successfully treated with intravenous immunoglobulin, corticosteroid and aspirin. Both patients had ectodermal and/or skeletal features overlapping those seen in RASopathies, supporting the observations of Alkhunaizi et al. 2018. on the clinical overlap between Helsmoortel-Van der Aa syndrome and Noonan syndrome. We observed a morphological overlap with the Noonan-like disorder with anagen hair in our patients.

Vineland Adaptive Behavior Scale in a Cohort of Four ADNP Syndrome Patients Implicates Age-Dependent Developmental Delays with Increased Impact of Activities of Daily Living

Activity-dependent neuroprotective protein (ADNP) is one of the lead genes in autism spectrum disorder/intellectual disability. Heterozygous, de novo ADNP mutations cause the ADNP syndrome. Here, to evaluate natural history of the syndrome, mothers of two ADNP syndrome boys aged 6 and a half and two adults aged 27 years (man and woman) were subjected to Vineland III questionnaire assessing adaptive behavior. The boys were assessed again about 2 years after the first measurements. The skill measures, presented as standard scores (SS) included domains of communication, daily living, socialization, motor skills and a sum of adaptive behavior composite. The age equivalent (AE) and growth scale values (GSV) encompassing 11 subdomains assess the age level at which the subject's raw score is found at a norm sample median and the individual temporal progression, respectively. The norm referenced standard scores age-matched, mean 100 ± 15 of the two children showed the lowest outcome in communication (SS: 20-30). Daily living skills presented SS of 50-60, with a possible potential loss of some activities as the child ages, especially in interpersonal relationships with people outside of the immediate family (boy A). In contrast, in socialization, both children were at the SS of 38, with some positive increase to SS of ~ 45 (interpersonal relations with family members and coping skills, depending on the particular individual), 2 years later. Interestingly, there was an apparent large difference in motor skills (gross and fine) at the young age, with subject B showing a relatively higher level of skills (SS: 70), decreasing to subject A level (SS: 40) 2 years later. Together, the adaptive behavior composite suggested a level of SS: 39-48 with B showing a potential increase (SS: 41-44) and A, a substantial decrease (SS: 48-39), suggesting a strong impact of daily living skills. Adults were at SS: 20, which is the lowest possible score. AE showed minor improvements for subject A and B, with all AE values being below 3 years. GSVs for subject A showed some improvement with age, especially in interpersonal, play and leisure, and gross motor subdomains. GSV for subject B showed minor improvements in the various subdomains. Notably, all subjects showed a percentile rank < 1 compared with age-matched norms except for subject B as to motor domain (2^nd percentile) at the age of 6 years. In summary, the results, especially comparing SS and AEs between childhood and adulthood, implied a continuous deterioration of activities compared to the general population, encompassing a slower developmental process coupled to possible neurodegeneration, strongly supporting a great need for disease modifying medicinal procedures.

Complex Diagnostics of Non-Specific Intellectual Developmental Disorder

Intellectual development disorder (IDD) is characterized by a general deficit in intellectual and adaptive functioning. In recent years, there has been a growing interest in studying the genetic structure of IDD. Of particular difficulty are patients with non-specific IDD, for whom it is impossible to establish a clinical diagnosis without complex genetic diagnostics. We examined 198 patients with non-specific IDD from 171 families using whole-exome sequencing and chromosome microarray analysis. Hereditary forms of IDD account for at least 35.7% of non-specific IDD, of which 26.9% are monogenic forms. Variants in the genes associated with the BAF (SWI/SNF) complex were the most frequently identified. We were unable to identify phenotypic features that would allow differential diagnosis of monogenic and microstructural chromosomal rearrangements in non-specific IDD at the stage of clinical examination, but due to its higher efficiency, exome sequencing should be the diagnostic method of the highest priority study after the standard examination of patients with NIDD in Russia.

OUP accepted manuscript

CHAMP1-related neurodevelopmental disorder, or CHAMP1 disorder, is a recently described genetic syndrome associated with developmental delay, intellectual disability, behavioral symptoms, medical comorbidities, and dysmorphic features. To date, literature has focused on medical review and dysmorphology but has yet to prospectively assess neurobehavioral core domains such as autism, or behavioral, language, cognitive, and sensory features. Here, we present deep phenotyping results for 11 individuals with CHAMP1 disorder, based on approximately 12 hours of remote clinician-administered assessments and standardized caregiver questionnaires. Diagnoses of autism spectrum disorder were given to 33% of participants; repetitive behaviors and sensory-seeking symptoms were prominent in this cohort. In addition, 60% of participants met the criteria for attention-deficit/hyperactivity disorder (ADHD). High rates of ADHD and relatively low rates of treatment suggest potential areas for intervention. This study represents the first prospective phenotyping analysis of individuals with CHAMP1 disorder. The utility of specific measures as clinical endpoints, as well as benefits and limitations of remote phenotyping, are described.

Oro-Dental Manifestations in a Pediatric Patient Affected by Helsmoortel-Van der Aa Syndrome

Aim: Aim of this case report is to describe oro-facial abnormalities in a patient affected by Helsmoortel-Van der Aa syndrome, a rare autism syndrome, with not well described dental and cranial malformations. Case Report: Helsmoortel-Van der Aa Syndrome is a rare autosomal genetic syndrome causing mental impairment and autism, craniofacial dysmorphism, chest deformity and multiple organs dysfunction. Oro-facial involvement in Helsmoortel-Van der Aa syndrome has not been thoroughly described yet. The present article reports a case of a 9 years old male patient affected by Helsmoortel-Van der Aa Syndrome, presenting with oral breathing typical facies, high arched palate, II class and dental crowding. The patient teething was adequate to his age. The enamel of incisors and molars showed demineralization areas and dark spots, a clinical picture consistent with molar incisor hypomineralization syndrome. These hypo-mineralized areas are more susceptible to cavities, in fact the patient’s 4.6 tooth was decayed. The child was brought to our attention due to a mucocele on the lower lip, confirmed by histopathologic examination. Available data on oro-dental manifestation of this syndrome are rather poor and inconsistent, also due to the rarity of the disease. The finding of enamel abnormalities in the presented case could suggest a potential genetic etiopathogenesis linked to the same genes causing Helsmoortel-Van der Aa syndrome.

The Aqueous Extract of Eucommia Leaves Promotes Proliferation, Differentiation, and Mineralization of Osteoblast-Like MC3T3-E1 Cells

Eucommia leaves are dry leaves of Eucommia ulmoides which have long been considered as a functional health food for the treatment of hypertension, hypercholesterolemia, fatty liver, and osteoporosis. With the recent development of Chinese medicine, Eucommia leaves are widely used for tonifying the kidneys and strengthening bone. However, the specific molecular mechanism of Eucommia leaves for strengthening bone remains largely unknown. Osteoblasts are the main functional cells of bone formation; thus, it is essential to study the effect of Eucommia leaves on osteoblasts to better understand their mechanism of action. In the present study, we prepared an aqueous extract of Eucommia leaves (ELAE) and determined its content by high-performance liquid chromatography (HPLC). The effects of ELAE on MC3T3-E1 cells were investigated by CCK-8 assay, alkaline phosphatase (ALP), and Alizarin red S staining assays, combined with RNA sequencing (RNA-seq) and qRT-PCR validation. We demonstrated that ELAE had a significant promoting effect on the proliferation of MC3T3-E1 cells and significantly enhanced extracellular matrix synthesis and mineralization, which were achieved by regulating various functional genes and related signaling pathways. ELAE significantly increased the expression level of genes promoting cell proliferation, such as Rpl10a, Adnp, Pex1, Inpp4a, Frat2, and Pcdhga1, and reduced the expression level of genes inhibiting cell proliferation, such as Npm1, Eif3e, Cbx3, Psmc6, Fgf7, Fxr1, Ddx3x, Mbnl1, and Cdc27. In addition, ELAE increased the expression level of gene markers in osteoblasts, such as Col5a2, Ubap2l, Dkk3, Foxm1, Col16a1, Col12a1, Usp7, Col4a6, Runx2, Sox4, and Bmp4. Taken together, our results suggest that ELAE could promote osteoblast proliferation, differentiation, and mineralization and prevent osteoblast apoptosis. These findings not only increase our understanding of ELAE on the regulation of bone development but also provide a possible strategy to further study the prevention and treatment of osteogenic related diseases by ELAE.

Discovery of autism/intellectual disability somatic mutations in Alzheimer's brains: mutated ADNP cytoskeletal impairments and repair as a case study

With Alzheimer's disease (AD) exhibiting reduced ability of neural stem cell renewal, we hypothesized that de novo mutations controlling embryonic development, in the form of brain somatic mutations instigate the disease. A leading gene presenting heterozygous dominant de novo autism-intellectual disabilities (ID) causing mutations is activity-dependent neuroprotective protein (ADNP), with intact ADNP protecting against AD-tauopathy. We discovered a genomic autism ADNP mutation (c.2188C>T) in postmortem AD olfactory bulbs and hippocampi. RNA-Seq of olfactory bulbs also identified a novel ADNP hotspot mutation, c.2187_2188insA. Altogether, 665 mutations in 596 genes with 441 mutations in AD patients (389 genes, 38% AD-exclusive mutations) and 104 genes presenting disease-causing mutations (OMIM) were discovered. OMIM AD mutated genes converged on cytoskeletal mechanisms, autism and ID causing mutations (about 40% each). The number and average frequencies of AD-related mutations per subject were higher in AD subjects compared to controls. RNA-seq datamining (hippocampus, dorsolateral prefrontal cortex, fusiform gyrus and superior frontal gyrus-583 subjects) yielded similar results. Overlapping all tested brain areas identified unique and shared mutations, with ADNP singled out as a gene associated with autism/ID/AD and presenting several unique aging/AD mutations. The large fusiform gyrus library (117 subjects) with high sequencing coverage correlated the c.2187_2188insA ADNP mutation frequency to Braak stage (tauopathy) and showed more ADNP mutations in AD specimens. In cell cultures, the ADNP-derived snippet NAP inhibited mutated-ADNP-microtubule (MT) toxicity and enhanced Tau-MT association. We propose a paradigm-shifting concept in the perception of AD whereby accumulating mosaic somatic mutations promote brain pathology.

Whole genome sequencing of 45 Japanese patients with intellectual disability

Intellectual disability (ID) is characterized by significant limitations in both intellectual functioning and adaptive behaviors, originating before the age of 18 years. However, the genetic etiologies of ID are still incompletely elucidated due to the wide range of clinical and genetic heterogeneity. Whole genome sequencing (WGS) has been applied as a single-step clinical diagnostic tool for ID because it detects genetic variations with a wide range of resolution from single nucleotide variants (SNVs) to structural variants (SVs). To explore the causative genes for ID, we employed WGS in 45 patients from 44 unrelated Japanese families and performed a stepwise screening approach focusing on the coding variants in the genes. Here, we report 12 pathogenic and likely pathogenic variants: seven heterozygous variants of ADNP, SATB2, ANKRD11, PTEN, TCF4, SPAST, and KCNA2, three hemizygous variants of SMS, SLC6A8, and IQSEC2, and one homozygous variant in AGTPBP1. Of these, four were considered novel. Furthermore, a novel 76 kb deletion containing exons 1 and 2 in DYRK1A was identified. We confirmed the clinical and genetic heterogeneity and high frequency of de novo causative variants (8/12, 66.7%). This is the first report of WGS analysis in Japanese patients with ID. Our results would provide insight into the correlation between novel variants and expanded phenotypes of the disease.

Sensory Reactivity Symptoms Are a Core Feature of ADNP Syndrome Irrespective of Autism Diagnosis

Background: Activity dependent neuroprotective protein (ADNP) syndrome is one of the most common single-gene causes of autism spectrum disorder (ASD) and intellectual disability, however, the phenotypes remain poorly described. Here we examine the sensory reactivity phenotype in children and adolescents with ADNP syndrome. Methods: Twenty-two individuals with ADNP syndrome received comprehensive clinical evaluations including standardized observations, caregiver interviews, and questionnaires to assess sensory reactivity symptoms. Relationships between sensory symptoms and age, sex, ASD, IQ, and adaptive behavior were examined. Genotype-phenotype correlations with the recurrent p.Tyr719* variant were also explored. Results: Sensory reactivity symptoms were observed and reported in all participants. A syndrome-specific phenotype was identified, characterized by high levels of sensory seeking across tactile, auditory, and visual domains. Tactile hyporeactivity, characterized by pain insensitivity, was reported in the majority of participants. Sensory symptoms were identified across individuals regardless of age, sex, IQ, adaptive ability, genetic variant, and most importantly, ASD status. No significant differences were identified between participants with and without the recurrent p.Tyr719* variant on any sensory measure. Conclusions: Sensory reactivity symptoms are a common clinical feature of ADNP syndrome. Quantifying sensory reactivity using existing standardized measures will enhance understanding of sensory reactivity in individuals with ADNP syndrome and will aid in clinical care. The sensory domain may also represent a promising target for treatment in clinical trials.

Single Cell ADNP Predictive of Human Muscle Disorders: Mouse Knockdown Results in Muscle Wasting

Activity-dependent neuroprotective protein (ADNP) mutations are linked with cognitive dysfunctions characterizing the autistic-like ADNP syndrome patients, who also suffer from delayed motor maturation. We thus hypothesized that ADNP is deregulated in versatile myopathies and that local ADNP muscle deficiency results in myopathy, treatable by the ADNP fragment NAP. Here, single-cell transcriptomics identified ADNP as a major constituent of the developing human muscle. ADNP transcript concentrations further predicted multiple human muscle diseases, with concentrations negatively correlated with the ADNP target interacting protein, microtubule end protein 1 (EB1). Reverting back to modeling at the single-cell level of the male mouse transcriptome, Adnp mRNA concentrations age-dependently correlated with motor disease as well as with sexual maturation gene transcripts, while Adnp expressing limb muscle cells significantly decreased with aging. Mouse Adnp heterozygous deficiency exhibited muscle microtubule reduction and myosin light chain (Myl2) deregulation coupled with motor dysfunction. CRISPR knockdown of adult gastrocnemius muscle Adnp in a Cas9 mouse resulted in treadmill (male) and gait (female) dysfunctions that were specifically ameliorated by treatment with the ADNP snippet, microtubule interacting, Myl2-regulating, NAP (CP201). Taken together, our studies provide new hope for personalized diagnosis/therapeutics in versatile myopathies.

Developmental Predictors of Cognitive and Adaptive Outcomes in Genetic Subtypes of Autism Spectrum Disorder

Approximately one-fourth of autism spectrum disorder (ASD) cases are associated with a disruptive genetic variant. Many of these ASD genotypes have been described previously, and are characterized by unique constellations of medical, psychiatric, developmental, and behavioral features. Development of precision medicine care for affected individuals has been challenging due to the phenotypic heterogeneity that exists even within each genetic subtype. In the present study, we identify developmental milestones that predict cognitive and adaptive outcomes for five of the most common ASD genotypes. Sixty-five youth with a known pathogenic variant involving ADNP, CHD8, DYRK1A, GRIN2B, or SCN2A genes participated in cognitive and adaptive testing. Exploratory linear regressions were used to identify developmental milestones that predicted cognitive and adaptive outcomes within each gene group. We hypothesized that the earliest and most predictive milestones would vary across gene groups, but would be consistent across outcomes within each genetic subtype. Within the ADNP group, age of walking predicted cognitive outcomes, while age of first words predicted adaptive behaviors. Age of phrases predicted adaptive functioning in the CHD8 group, but cognitive outcomes were not clearly associated with early developmental milestones. Verbal milestones were the strongest predictors of cognitive and adaptive outcomes for individuals with mutations to DYRK1A, GRIN2B, or SCN2A. These trends inform decisions about treatment planning and long-term expectations for affected individuals, and they add to the growing body of research linking molecular genetic function to brain development and phenotypic outcomes. LAY SUMMARY: Researchers have found many genetic causes of autism including mutations to ADNP, CHD8, DYRK1A, GRIN2B, and SCN2A genes. We found that each genetic cause had different early developmental milestones that explained the overall functioning of the children when they were older. Depending on the genetic cause, the age that a child first starts walking and/or talking may help to better understand and support a child's development who has a mutation to one of the above genes. Autism Res 2020, 13: 1659-1669. © 2020 International Society for Autism Research and Wiley Periodicals LLC.

Age and Sex-Dependent ADNP Regulation of Muscle Gene Expression Is Correlated with Motor Behavior: Possible Feedback Mechanism with PACAP

The activity-dependent neuroprotective protein (ADNP), a double-edged sword, sex-dependently regulates multiple genes and was previously associated with the control of early muscle development and aging. Here we aimed to decipher the involvement of ADNP in versatile muscle gene expression patterns in correlation with motor function throughout life. Using quantitative RT-PCR we showed that Adnp^+/− heterozygous deficiency in mice resulted in aberrant gastrocnemius (GC) muscle, tongue and bladder gene expression, which was corrected by the Adnp snippet, drug candidate, NAP (CP201). A significant sexual dichotomy was discovered, coupled to muscle and age-specific gene regulation. As such, Adnp was shown to regulate myosin light chain (Myl) in the gastrocnemius (GC) muscle, the language acquisition gene forkhead box protein P2 (Foxp2) in the tongue and the pituitary-adenylate cyclase activating polypeptide (PACAP) receptor PAC1 mRNA (Adcyap1r1) in the bladder, with PACAP linked to bladder function. A tight age regulation was observed, coupled to an extensive correlation to muscle function (gait analysis), placing ADNP as a muscle-regulating gene/protein.

Disturbances in primary dental enamel in Polish autistic children

Dental enamel is a structure that is formed as a result of the regular functioning of ameloblasts. The knowledge of the patterns of enamel secretion allows an analysis of their disruptions manifested in pronounced additional accentuated lines. These lines represent a physiological response to stress experienced during enamel development. The aim of this study was to assess the occurrence of accentuated lines in the tooth enamel of autistic boys. The width of the neonatal line and the periodicity of the striae of Retzius were also assessed. The study material consisted of longitudinal ground sections of 56 primary teeth (incisors and molars): 22 teeth from autistic children and 34 teeth from the control group. The Mann-Whitney U test indicates that the accentuated lines were found significantly more often in autistic children (Z = 3.03; p = 0.002). No differentiation in the rate of enamel formation and in the rate of regaining homeostasis after childbirth were found. The obtained results may indicate a higher sensitivity of autistic children to stress factors, manifested in more frequent disturbances in the functioning of ameloblasts or may be a reflection of differences in the occurrence of stress factors in the first years of life in both analyzed groups.

Early behavioral and developmental interventions in ADNP-syndrome: A case report of SWI/SNF-related neurodevelopmental syndrome

Background

Autism spectrum disorder (ASD) affects approximately one in 59 children. Variants in the activity‐dependent neuroprotector homeobox ADNP (OMIM #611386) gene may be one of the most common single‐gene causes of syndromic ASD. Most patients diagnosed with ADNP syndrome have ASD as a comorbidity, and all patients have mild‐to‐severe intellectual disability.

Methods/Case Report

We present a case report of a patient diagnosed with ADNP syndrome at 2.5 years of age. The patient has many of the key features of the syndrome, including ASD, global developmental delay, behavioral problems, congenital heart defect, early tooth eruption, and vision problems. The patient's initial presentation included congenital diaphragmatic hernia (CDH), which has not been previously reported in this condition.

Results

The patient exhibited frequent behavioral outbursts and was initiated on antipsychotic medication with near‐complete resolution of symptoms allowing her to engage more fully in early intervention therapies leading to progress in language acquisition.

Conclusion

This short report provides guidance for antipsychotic medication dosing to improve early intervention outcomes. This is the first report of CDH in this syndrome.

Microbiota changes associated with ADNP deficiencies: rapid indicators for NAP (CP201) treatment of the ADNP syndrome and beyond

Activity-dependent neuroprotective protein (ADNP) and its protein snippet NAP (drug candidate CP201) regulate synapse formation and cognitive as well as behavioral functions, in part, through microtubule interaction. Given potential interactions between the microbiome and brain function, we now investigated the potential effects of the ADNP-deficient genotype, mimicking the ADNP syndrome on microbiota composition in the Adnp^+/– mouse model. We have discovered a surprising robust sexually dichotomized Adnp genotype effect and correction by NAP (CP201) as follows. Most of the commensal bacterial microbiota tested were affected by the Adnp genotype and corrected by NAP treatment in a male sex-dependent manner. The following list includes all the bacterial groups tested—labeled in bold are male Adnp—genotype increased and corrected (decreased) by NAP. (1) Eubacteriaceae (EubV3), (2) Enterobacteriaceae (Entero), (3) Enterococcus genus (gEncocc), (4) Lactobacillus group (Lacto), (5) Bifidobacterium genus (BIF), (6) Bacteroides/Prevotella species (Bac), (7) Clostridium coccoides group (Coer), (8) Clostridium leptum group (Cluster IV, sgClep), and (9) Mouse intestinal Bacteroides (MIB). No similarities were found between males and females regarding sex- and genotype-dependent microbiota distributions. Furthermore, a female Adnp^+/– genotype associated decrease (contrasting male increase) was observed in the Lactobacillus group (Lacto). Significant correlations were discovered between specific bacterial group loads and open-field behavior as well as social recognition behaviors. In summary, we discovered ADNP deficiency associated changes in commensal gut microbiota compositions, a sex-dependent biomarker for the ADNP syndrome and beyond. Strikingly, we discovered rapidly detected NAP (CP201) treatment-dependent biomarkers within the gut microbiota.

PANDA: Prioritization of autism-genes using network-based deep-learning approach

Understanding the genetic background of complex diseases and disorders plays an essential role in the promising precision medicine. The evaluation of candidate genes, however, requires time-consuming and expensive experiments given a large number of possibilities. Thus, computational methods have seen increasing applications in predicting gene-disease associations. We proposed a bioinformatics framework, Prioritization of Autism-genes using Network-based Deep-learning Approach (PANDA). Our approach aims to identify autism-genes across the human genome based on patterns of gene-gene interactions and topological similarity of genes in the interaction network. PANDA trains a graph deep learning classifier using the input of the human molecular interaction network and predicts and ranks the probability of autism association of every node (gene) in the network. PANDA was able to achieve a high classification accuracy of 89%, outperforming three other commonly used machine learning algorithms. Moreover, the gene prioritization ranking list produced by PANDA was evaluated and validated using an independent large-scale exome-sequencing study. The top 10% of PANDA-ranked genes were found significantly enriched for autism association.

VIP/PACAP-Based Drug Development: The ADNP/NAP-Derived Mirror Peptides SKIP and D-SKIP Exhibit Distinctive in vivo and in silico Effects

Activity-dependent neuroprotective protein (ADNP) was discovered and first characterized in the laboratory of Prof. Illana Gozes to be regulated by vasoactive intestinal peptide (VIP), and pituitary adenylate cyclase-activating peptide (PACAP) toward neuroprotection. Importantly, ADNP is a master regulator of >400 genes, essential for brain formation, while its haploinsufficiency causes cognitive impairments. Recently, de novo mutations in ADNP were identified as leading to the autism-like ADNP syndrome, mimicked by the Adnp-deficient mouse model. Furthermore, novel peptide derivatives of the neuroprotective ADNP-snippet NAP (NAPVSIPQ), developed in our laboratory, include SKIP and the mirroring all D-amino acid SKIP (D-SKIP). We now extended previous evidence suggesting potential antagonistic features for D-SKIP, compared with the neuroprotective peptide SKIP, as was observed by NMR analysis and social/olfactory functional testing. Here, an impact of the Adnp genotype was observed in the Morris Water Maze (MWM) test measuring cognition, coupled with improvement by SKIP, opposing the inert/exacerbating effect of D-SKIP. In the elevated plus-maze and open field tests measuring anxiety-related behaviors, contrasting effects of SKIP and D-SKIP were found, with SKIP improving/preserving the normal phenotype of the mouse, and D-SKIP causing alterations. Lastly, an in silico analysis suggested that SKIP and D-SKIP bind the microtubule end binding (EB) proteins EB1 and EB3 in different conformations, thereby indicating distinctive natures for the two peptides, potentially mediating differential in vivo effects. Altogether, our findings corroborate the notion of D-SKIP acting as an antagonist, thus distinguishing it from the neuroprotective SKIP.

The autism-mutated ADNP plays a key role in stress response

Activity-dependent neuroprotective protein (ADNP), discovered and first characterized in our laboratory (IG), is vital for mammalian brain formation and presents one of the leading genes mutated de novo causing an autistic syndrome, namely the ADNP syndrome. Furthermore, a unique mouse model of Adnp-haploinsufficiency was developed in the laboratory (IG), with mice exhibiting cognitive and social deficiencies. ADNP is regulated by vasoactive intestinal peptide (VIP), and pituitary adenylate cyclase-activating peptide (PACAP). In this respect, PACAP was independently identified as a sexual divergent master regulator of the stress response. Here, we sought to determine the impact of the Adnp genotype and the efficacy of PACAP pre-treatment when subjecting Adnp^+/- mice to stressful conditions. Significant sex differences were observed with Adnp^+/- males being more susceptible to stress in the object and social recognition tests, and the females more susceptible in the open field and elevated plus maze tests. Splenic Adnp expression and plasma cortisol levels in mice were correlated with cognition (male mice) and anxiety-related behavior. These findings were further translated to humans, with observed correlations between ADNP expression and stress/cortisol content in a young men cohort. Altogether, our current results may establish ADNP as a marker of stress response.

ADNP differentially interact with genes/proteins in correlation with aging: a novel marker for muscle aging

Activity-dependent neuroprotective protein (ADNP) is essential for embryonic development with ADNP mutations leading to syndromic autism, coupled with intellectual disabilities and motor developmental delays. Here, mining human muscle gene-expression databases, we have investigated the association of ADNP transcripts with muscle aging. We discovered increased ADNP and its paralogue ADNP2 expression in the vastus lateralis muscle of aged compared to young subjects, as well as altered expression of the ADNP and the ADNP2 genes in bicep brachii muscle of elderly people, in a sex-dependent manner. Prolonged exercise resulted in decreased ADNP expression, and increased ADNP2 expression in an age-dependent manner in the vastus lateralis muscle. ADNP expression level was further correlated with 49 genes showing age-dependent changes in muscle transcript expression. A high degree of correlation with ADNP was discovered for 24 genes with the leading gene/protein being NMNAT1 (nicotinamide nucleotide adenylyl transferase 1). Looking at correlations differentiating the young and the old muscles and comparing protein interactions revealed an association of ADNP with the cell division cycle 5-like protein (CDC5L), and an aging-muscle-related interactive pathway in the vastus lateralis. In the bicep brachii, very high correlation was detected with genes associated with immune functions as well as mitochondrial structure and function among others. Taken together, the results suggest a direct association of ADNP with muscle strength and implicate ADNP fortification in the protection against age-associated muscle wasting.

Roles of SP600125 in expression of JNK, RANKL and OPG in cultured dental follicle cells

OBJECTIVE

To investigate the expression of C-JNK, RANKL and OPG after SP600125 administration in cultured dental follicle cells (DFCs).

METHODS

TRAP staining and electron microscope were carried out on day 7 and 9 after coculture of BMMs and DFCs with a ratio of 5:1 in different groups. To determine the effects of SP600125 on the expression of C-JNK, RANKL and OPG mRNA and protein, cultured DFCs were divided into control group, DMSO group and SP600125 groups. Real-time PCR and Western blot analysis were performed to investigate the expression of the mRNA and protein, respectively.

RESULTS

TRAP assay indicated that the number of multinucleated osteoclasts in the SP600125 group showed significant decrease compared with that of control (P < 0.05). The expression of JNK protein in the SP600125 groups showed significant decline compared with that of the control group and blank control (P < 0.05). Significant decrease was noticed in the RANKL protein expression with the elevation of SP600125.

CONCLUSIONS

SP600125 could inhibit the formation of osteoclast in the coculture system of DFCs and BMMs. After SP600125 treatment, the expression of RANKL and JNK showed a trend of decrease, and the expression of OPG showed gradual increase followed by gradual decrease.

Clinical Presentation of a Complex Neurodevelopmental Disorder Caused by Mutations in ADNP

BACKGROUND

In genome-wide screening studies for de novo mutations underlying autism and intellectual disability, mutations in the ADNP gene are consistently reported among the most frequent. ADNP mutations have been identified in children with autism spectrum disorder comorbid with intellectual disability, distinctive facial features, and deficits in multiple organ systems. However, a comprehensive clinical description of the Helsmoortel-Van der Aa syndrome is lacking.

METHODS

We identified a worldwide cohort of 78 individuals with likely disruptive mutations in ADNP from January 2014 to October 2016 through systematic literature search, by contacting collaborators, and through direct interaction with parents. Clinicians filled in a structured questionnaire on genetic and clinical findings to enable correlations between genotype and phenotype. Clinical photographs and specialist reports were gathered. Parents were interviewed to complement the written questionnaires.

RESULTS

We report on the detailed clinical characterization of a large cohort of individuals with an ADNP mutation and demonstrate a distinctive combination of clinical features, including mild to severe intellectual disability, autism, severe speech and motor delay, and common facial characteristics. Brain abnormalities, behavioral problems, sleep disturbance, epilepsy, hypotonia, visual problems, congenital heart defects, gastrointestinal problems, short stature, and hormonal deficiencies are common comorbidities. Strikingly, individuals with the recurrent p.Tyr719* mutation were more severely affected.

CONCLUSIONS

This overview defines the full clinical spectrum of individuals with ADNP mutations, a specific autism subtype. We show that individuals with mutations in ADNP have many overlapping clinical features that are distinctive from those of other autism and/or intellectual disability syndromes. In addition, our data show preliminary evidence of a correlation between genotype and phenotype.

Atypical Auditory Brainstem Response and Protein Expression Aberrations Related to ASD and Hearing Loss in the Adnp Haploinsufficient Mouse Brain

Autism is a wide spread neurodevelopmental disorder with growing morbidity rates, affecting more boys than girls worldwide. Activity-dependent neuroprotective protein (ADNP) was recently recognized as a leading gene accounted for 0.17% of autism spectrum disorder (ASD) cases globally. Respectively, mutations in the human ADNP gene (ADNP syndrome), cause multi-system body dysfunctions with apparent ASD-related traits, commencing as early as childhood. The Adnp haploinsufficient (Adnp^+/-) mouse model was researched before in relations to Alzheimer's disease and autism. Adnp^+/- mice suffer from deficient social memory, vocal and motor impediments, irregular tooth eruption and short stature, all of which corresponds with reported phenotypes in patients with the ADNP syndrome. Recently, a more elaborated description of the ADNP syndrome was published, presenting impediments such as hearing disabilities in > 10% of the studied children. Irregular auditory brainstem response (ABR) has been connected to ASD-related cases and has been suggested as a potential hallmark for autism, allowing diagnosis of ASD risk and early intervention. Herein, we present detriment hearing in the Adnp^+/- mice with atypical ABR and significant protein expression irregularities that coincides with ASD and hearing loss studies in the brain.

Synaptic metabolism: a new approach to inborn errors of neurotransmission

To date, inborn errors of neurotransmitters have been defined based on the classic concept of inborn error of metabolism (IEM), and they include defects in synthesis, catabolism, and transport pathways. However, the omics era is bringing insights into new diseases and is leading to an extended definition of IEM including new categories and mechanisms. Neurotransmission takes place at the synapse, the most specialized tight junction in the brain. The concept of "synaptic metabolism" would point to the specific chemical composition and metabolic functions of the synapse. Based on these specialized functions, we aim to provide a tentative overview about the major categories of IEM susceptible to affect neurotransmission. Small molecule defects (biogenic amines and amino acids) and energy defects are amongst the most prevalent diseases reported to disturb the concentration of CSF neurotransmitters. In these IEM, the neurological phenotypes have been largely described. Disorders of complex molecules are not typically considered as diseases affecting neurotransmission. However, most of them have been recently discovered and are involved in intracellular vesiculation, trafficking, processing, and quality control mechanisms. In this large group, neurotransmission is affected in disorders of chaperones and autophagy, disorders of the synaptic vesicle, and diseases affecting pre-synaptic membranes (synthesis and remodeling of complex lipids, defects of glycosylation). Disorders of the vesicle pools, receptor trafficking, and the chronobiology of neurotransmission are potentially emerging new categories. Finally, although not considered as IEM, channelopathies are a large group of diseases disturbing neurotransmitter homeostasis. New CSF biomarkers will probably contribute to improve the diagnosis of these disorders and find new therapeutic targets.

Activity-dependent neuroprotective protein deficiency models synaptic and developmental phenotypes of autism-like syndrome

Previous findings showed that in mice, complete knockout of activity-dependent neuroprotective protein (ADNP) abolishes brain formation, while haploinsufficiency (Adnp+/-) causes cognitive impairments. We hypothesized that mutations in ADNP lead to a developmental/autistic syndrome in children. Indeed, recent phenotypic characterization of children harboring ADNP mutations (ADNP syndrome children) revealed global developmental delays and intellectual disabilities, including speech and motor dysfunctions. Mechanistically, ADNP includes a SIP motif embedded in the ADNP-derived snippet drug candidate NAP (NAPVSIPQ, also known as CP201), which binds to microtubule end-binding protein 3, essential for dendritic spine formation. Here, we established a unique neuronal membrane-tagged, GFP-expressing Adnp+/- mouse line allowing in vivo synaptic pathology quantification. We discovered that Adnp deficiency reduced dendritic spine density and altered synaptic gene expression, both of which were partly ameliorated by NAP treatment. Adnp+/-mice further exhibited global developmental delays, vocalization impediments, gait and motor dysfunctions, and social and object memory impairments, all of which were partially reversed by daily NAP administration (systemic/nasal). In conclusion, we have connected ADNP-related synaptic pathology to developmental and behavioral outcomes, establishing NAP in vivo target engagement and identifying potential biomarkers. Together, these studies pave a path toward the clinical development of NAP (CP201) for the treatment of ADNP syndrome.

The autism spectrum phenotype in ADNP syndrome

Pathogenic disruptions to the activity-dependent neuroprotector homeobox (ADNP) gene are among the most common heterozygous genetic mutations associated with autism spectrum disorders (ASDs). Individuals with ADNP disruptions share a constellation of medical and psychiatric features, including ASD, intellectual disability (ID), dysmorphic features, and hypotonia. However, the profile of ASD symptoms associated with ADNP may differ from that of individuals with another ASD-associated single gene disruption or with ASD without a known genetic cause. The current study examined the ASD phenotype in a sample of representative youth with ADNP disruptions. Participants (N = 116, ages 4-22 years) included a cohort with ADNP mutations (n = 11) and three comparison groups with either a mutation to CHD8 (n = 11), a mutation to another ASD-associated gene (other mutation; n = 53), or ASD with no known genetic etiology (idiopathic ASD; n = 41). As expected, individuals with ADNP disruptions had higher rates of ID but less severe social affect symptoms compared to the CHD8 and Idiopathic ASD groups. In addition, verbal intelligence explained more variance in social impairment in the ADNP group compared to CHD8, other mutation, and idiopathic ASD comparison groups. Restricted and repetitive behaviors in the ADNP group were characterized by high levels of stereotyped motor behaviors, whereas the idiopathic ASD group showed high levels of restricted interests. Taken together, these results underscore the role of ADNP in cognitive functioning and suggest that social impairments in ADNP syndrome are consistent with severity of verbal deficits. Autism Res 2018, 11: 1300-1310. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Disruptions to the ADNP gene (i.e., ADNP syndrome) have been associated with autism spectrum disorder (ASD). This article describes intellectual disability, mild social difficulties, and severe repetitive motor movements in a group of 11 youth with ADNP Syndrome. We found lower rates of ASD than previously reported. Verbal skills explained individual variability in social impairment. This pattern suggests that the ADNP gene is primarily associated with learning and memory, and level of social difficulties is consistent with level of verbal impairment.

Repositioning Microtubule Stabilizing Drugs for Brain Disorders

Microtubule stabilizing agents are among the most clinically useful chemotherapeutic drugs. Mostly, they act to stabilize microtubules and inhibit cell division. While not without side effects, new generations of these compounds display improved pharmacokinetic properties and brain penetrance. Neurological disorders are intrinsically associated with microtubule defects, and efforts to reposition microtubule-targeting chemotherapeutic agents for treatment of neurodegenerative and psychiatric illnesses are underway. Here we catalog microtubule regulators that are associated with Alzheimer's and Parkinson's disease, amyotrophic lateral sclerosis, schizophrenia and mood disorders. We outline the classes of microtubule stabilizing agents used for cancer treatment, their brain penetrance properties and neuropathy side effects, and describe efforts to apply these agents for treatment of brain disorders. Finally, we summarize the current state of clinical trials for microtubule stabilizing agents under evaluation for central nervous system disorders.

The Role of the Microtubule Cytoskeleton in Neurodevelopmental Disorders

Neurons depend on the highly dynamic microtubule (MT) cytoskeleton for many different processes during early embryonic development including cell division and migration, intracellular trafficking and signal transduction, as well as proper axon guidance and synapse formation. The coordination and support from MTs is crucial for newly formed neurons to migrate appropriately in order to establish neural connections. Once connections are made, MTs provide structural integrity and support to maintain neural connectivity throughout development. Abnormalities in neural migration and connectivity due to genetic mutations of MT-associated proteins can lead to detrimental developmental defects. Growing evidence suggests that these mutations are associated with many different neurodevelopmental disorders, including intellectual disabilities (ID) and autism spectrum disorders (ASD). In this review article, we highlight the crucial role of the MT cytoskeleton in the context of neurodevelopment and summarize genetic mutations of various MT related proteins that may underlie or contribute to neurodevelopmental disorders.

Longitudinal ophthalmic findings in a child with Helsmoortel-Van der Aa Syndrome

Purpose

We present the first detailed ophthalmic description of a child with Helsmoortel-Van der Aa Syndrome (HVDAS), including longitudinal follow-up and analysis.

Observations

After extensive workup, a young child with poor visual behavior, hypotonic cerebral palsy, intellectual disability, and global developmental delay was found to have a heterozygous de novo mutation in the ADNP gene and diagnosed with HVDAS. Ophthalmic findings were remarkable for progressive nystagmus, macular pigment mottling, mild foveal hypoplasia with abnormal macular laminations, persistent rod dysfunction with electronegative waveform, and progressive cone degeneration.

Conclusions and importance

Patients with HVDAS are known to have abnormal visual behavior due to refractive or cortical impairment. However, we present the first description, to our knowledge, of an association with retinal mal-development and degeneration. Thus, patients with HVDAS should be referred for ophthalmic genetics evaluation, and HVDAS should be on the differential diagnosis for young children with global developmental delay who present with nystagmus, rod and cone dysfunction with electronegative waveform, and relative lack of severe structural degeneration on optical coherence tomography.

ADNP Plays a Key Role in Autophagy: From Autism to Schizophrenia and Alzheimer's Disease

Activity-dependent neuroprotective protein (ADNP), discovered in our laboratory in 1999, has been characterized as a master gene vital for mammalian brain formation. ADNP de novo mutations in humans result in a syndromic form of autism-like spectrum disorder (ASD), including cognitive and motor deficits, the ADNP syndrome (Helsmoortel-Van Der Aa). One of the most important cellular processes associated with ADNP is the autophagy pathway, recently discovered by us as a key player in the pathophysiology of schizophrenia. In this regard, given the link between the microtubule and autophagy systems, the ADNP microtubule end binding protein motif, namely, the neuroprotective NAP (NAPVSIPQ), was found to enhance autophagy while protecting microtubules and augmenting ADNP's association with both systems. Thus, linking autophagy and ADNP is proposed as a major target for intervention in brain diseases from autism to Alzheimer's disease (AD) and our findings introduce autophagy as a possible novel target for treating schizophrenia.