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The neurometabolic disorder known as biotin-thiamine-responsive basal ganglia disease (BTBGD) is a rare autosomal recessive condition linked to bi-allelic pathogenic mutations in the SLC19A3 gene. BTBGD is characterized by progressive encephalopathy, confusion, seizures, dysarthria, dystonia, and severe disabilities. Diagnosis is difficult due to the disease's rare nature and diverse clinical characteristics. The primary treatment for BTBGD at this time is thiamine and biotin supplementation, while its long-term effectiveness is still being investigated. In this study, we have generated two clones of induced pluripotent stem cells (iPSCs) from a 10-year-old female BTBGD patient carrying a homozygous mutation for the pathogenic variant in exon 5 of the SLC19A3 gene, c.1264A > G (p.Thr422Ala). We have confirmed the pluripotency of the generated iPS lines and successfully differentiated them to neural progenitors. Because our understanding of genotype-phenotype correlations in BTBGD is limited, the establishment of BTBGD-iPSC lines with a homozygous SLC19A3 mutation provides a valuable cellular model to explore the molecular mechanisms underlying SLC19A3-associated cellular dysfunction. This model holds potential for advancing the development of novel therapeutic strategies., (© 2024. The Author(s).)

Background : Biotin-thiamine-responsive basal ganglia disease (BTBGD) is a rare, treatable autosomal recessive neurometabolic disorder. This condition eventually leads to severe disability and death if not treated correctly. The clinical features of BTBGD, especially those with unusual complications, are not widely known by neurologists or pediatricians. Case presentation : A 4-month-old male infant was admitted to the hospital with a history of cough for the past 7 days and convulsions of 6 h duration. Physical examination showed confusion, bilateral pupillary light reflex delays, hypertonia of limbs, and brisk tendon reflexes of the limbs. Brain magnetic resonance imaging (MRI) showed multiple abnormal signals in the bilateral basal ganglia, lobes, corpus callosum, brainstem, and brain atrophy. However, his condition continued to worsen. Computed tomography performed 3 months later showed severe subdural hematoma and effusion. Subsequently, he underwent puncture drainage; however, his condition did not improve postoperatively. Repeated MRIs showed increasing subdural hematoma and effusion, and brain atrophy. The patient was diagnosed with BTBGD following whole-genome sequencing, which identified a novel compound heterozygous mutation of SLC19A3 gene. He was treated with biotin and thiamine, and the symptoms gradually improved. Subsequent MRIs showed a decrease in the subdural hematoma and effusion and partial improvement in brain atrophy. Conclusion: To the best of our knowledge, this is the first reported case of BTBGD, complicated by severe subdural hematoma. These observations extend our understanding of the clinical features, neuroimaging spectrum, and gene mutation spectrum of BTBGD. The phenotypic spectrum and pathophysiology of BTBGD are not completely understood and need to be studied further.

Biotin thiamine responsive basal ganglia disease (BTRBGD) is an inherited autosomal recessive disorder that results from the inability of thiamine to cross the blood-brain barrier. It is considered a treatable condition if vitamin supplementation, most commonly with thiamine and biotin, is initiated early. BTRBGD can present as an infantile form, classical childhood form, or adult Wernicke-like encephalopathy. The infantile form is often the most severe and portends a worse prognosis with high mortality despite vitamin supplementation. We present a two-month-old who presented with irritability, opisthotonos, and abnormal eye movements who was found to have compound heterozygous variants in the SLC19A3 gene inherited in trans, including one known pathogenic intronic variant and a novel variant presumed to be pathogenic. She was therefore diagnosed with infantile BTRBGD. In this report, we discuss the differential for infantile BTRBGD, the clinical and radiologic features of BTRBGD, and describe a rapid, positive response to early vitamin supplementation in an infant with a likely pathogenic novel variant in SLC19A3 ., (© 2023 American Academy of Neurology.)

Maternally inherited diabetes and deafness (MIDD) is a rare diabetic syndrome mainly caused by a point mutation in the mitochondrial DNA. It affects up to 1% of patients with diabetes but is often unrecognized by physicians. We report a case of MIDD in a 29-year-old man with coexisting imaging of cerebellar vermis hypoplasia and bilateral basal ganglia calcification., (© 2022. Fondazione Società Italiana di Neurologia.)

Primary brain calcification (PBC), also known as idiopathic basal ganglia calcification (IBGC), primary familial brain calcification (PFBC) and so on, is a rare intractable disease characterized by abnormal mineral deposits, including mostly calcium in the basal ganglia, thalamus, and cerebellum. The causative gene of familial PBC is SLC20A2, which encodes the phosphate transporter PiT-2. Despite this knowledge, the molecular mechanism underlying SLC20A2-associated PBC remains unclear. In the present study, we investigated whether haploinsufficiency or a dominant-negative mechanism reduced Pi uptake in two PiT-2 variants (T115 M and R467X). We demonstrated that the presence of T115 M or R467X had no dominant-negative effect on Pi transport activity of wild-type (WT). In addition, the subcellular localization of R467X completely differed from that of WT, indicating that there is no interaction between R467X and WT. Conversely, T115 M and WT showed almost the same localization. Therefore, we examined the interaction between T115 M and WT using the bioluminescence resonance energy transfer (BRET) method. Although WT and T115 M interact with each other, T115 M does not inhibit WT's Pi transport activity. These results suggest that the role of SLC20A2 in the pathogenesis of PBC may involve decreased intracellular Pi uptake by a haploinsufficiency mechanism rather than a dominant-negative mechanism; agents promoting PiT-2 dimerization may be promising potential therapeutic agents for PBC., Competing Interests: Declaration of competing interest The authors declared no conflict of interest., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Idiopathic basal ganglia calcification (IBGC) is a genetic disorder of the nervous system commonly known as Fahr disease. IBGC patients with a genetic background are considered to have primary familial brain calcification (PFBC), also known as familial basal ganglia calcification (FBGC), or familial Fahr disease. It is a rare degenerative neurological disorder characterized by extensive bilateral basal ganglia calcification that can lead to a range of extrapyramidal symptoms and neuropsychiatric manifestations. Studies have suggested that more than 50 variants of SLC20A2 gene mutations account for approximately 50% of IBGC cases. There is a wide spectrum of mutation types, including frameshift, nonsense, and splice site mutations in addition to deletion and missense mutations. Here we report a case of familial basal ganglia calcification caused by a frameshift mutation in the SLC20A2 gene. We identified a heterozygous mutation in the SLC20A2 gene, c.1097delG (p.G366fs*89). To our knowledge, this mutation site has not been reported before., Case Presentation: A 57-year-old male patient was admitted to the hospital with "unstable walking and involuntary movements between the eyes and eyebrows for 6 months". Based on the patient's family history, symmetrical calcification foci in the bilateral caudate nucleus head, thalamus, cerebellum and parietal lobe indicated by head CT, and gene test results, the diagnosis of familial Fahr disease caused by mutations in the SLC20A2 gene, c.1097delG p.G366fs*89) was confirmed., Conclusion: For the first time, we identified c.1097delG (p.G366fs*89) as a frameshift mutation in the IBGC family. This frameshift mutation caused the condition in this family of patients. This mutation not only broadens the range of known SLC20A2 mutations but also aids in the genetic diagnosis of IBGC., (© 2022. The Author(s).)

Fahr's disease (FD) is a neurodegenerative disorder characterized by symmetric calcifications in the bilateral basal ganglia and dentate nuclei. Mutations in six genes are known to cause FD. In the present case, a 44-year-old woman was admitted because of bradykinesia that had started developing 3 years ago. Brain CT and MRI revealed severe calcification in the bilateral basal ganglia, thalamus, dentate nuclei, and subcortical white matter. Whole-exome sequencing revealed two previously described compound heterozygous mutations within the MYORG gene. About one year later, the patient developed sudden-onset left-sided hemiparesis. The MRI revealed a small infarction in the right internal capsule. Therefore, the present case findings expand the clinical spectrum of FD. Importantly, the association between ischemic stroke and FD needs to be further studied., (Copyright: © Neurosciences.)

Purpose: Woodhouse-Sakati syndrome is a rare autosomal recessive syndrome caused by homozygous mutations in the DCAF17 gene, characterized by marked neurologic and endocrine manifestations in the setting of brain iron accumulation and white matter lesions on neuroimaging. Here, we report electrophysiologic profiles in Woodhouse-Sakati syndrome and their possible value in understanding disease pathophysiology and phenotypic variability., Methods: Thirteen genetically confirmed Woodhouse-Sakati syndrome patients were evaluated via different evoked potential (EP) modalities, including brainstem auditory EPs, pattern reversal visual EPs, and somatosensory EPs to tibial and/or median nerves., Results: All EP modalities showed variable abnormalities. Pattern reversal visual EPs were recorded in all patients, with nine patients exhibiting abnormal results. From those, seven patients showed prolonged P100 latencies after stimulation of right and left eyes for each in turn. Two patients showed P100 latency abnormality after single eye stimulation recorded from midoccipital electrode. Median somatosensory EPs were recorded in 10 patients, with 6 patients having a prolonged cortical N19 response. Tibial somatosensory EP was performed for 11 patients, and 8 patients showed abnormal results where P37 cortical response was absent or prolonged, whereas peripheral potentials at the popliteal fossa were normal. Brainstem auditory EPs were abnormal only in two patients, with prolonged wave III and V latencies. Five patients with hearing impairment presented with normal brainstem auditory EP results., Conclusions: Multiple EP abnormalities are observed in Woodhouse-Sakati syndrome patients, mainly in pattern reversal visual EPs and somatosensory EPs. These findings indicate potential myelin dysfunction that has a role in the underlying pathophysiology, disease course, and phenotypic variability., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2020 by the American Clinical Neurophysiology Society.)

Background: Primary familial brain calcification (PFBC) is a rare inherited neurological disorder characterized by bilateral basal ganglia calcification with a series of motor and nonmotor symptoms. Mutations in the SLC20A2 gene, encoding the PiT2 protein, are the major cause of the disease. Here, we report a Chinese PFBC family carrying a SLC20A2 gene mutation, and the proband presented with purely acute psychiatric symptoms, which has been rarely reported in this disease., Case Presentation: A 38-year-old woman was hospitalized due to disorganized speech; disordered thought contents; disorganized behaviour; emotional instability and lability; and grandiose words, actions and facial expressions. Brain computerized tomography (CT) revealed calcification in the basal ganglia; cerebellar dentate nuclei; and subcortical, periventricular, and deep white matter regions in she and her family members. Through mutation analysis, a heterozygous truncating mutation, c.1723G > T, p.(Glu575*), was identified in the SLC20A2 gene in this family. Thus, this patient was diagnosed with genetically confirmed PFBC, and she responded well to a low dose of antipsychotic drugs. The penetrance of the disease in this family was only 33%, which was significantly lower than that in most families carrying SLC20A2 gene mutations., Conclusions: Patients with SLC20A2-related PFBC might present with psychiatric symptoms alone, and the penetrance of the disease may be quite low, which adds to the clinical heterogeneity of the disease., (© 2022. The Author(s).)

Aim: To correlate clinical, radiological, and biochemical features with genetic findings in children with bilateral basal ganglia lesions of unknown aetiology, and propose a diagnostic algorithm for early recognition., Method: Children with basal ganglia disease were recruited in a 2-year prospective multicentre study for clinical, biomarker, and genetic studies. Radiological pattern recognition was examined by hierarchical clustering analysis., Results: We identified 22 genetic conditions in 30 out of 62 paediatric patients (37 males, 25 females; mean age at onset 2y, SD 3; range 0-10y; mean age at assessment 11y, range 1-25y) through gene panels (n=11), whole-exome sequencing (n=13), and mitochondrial DNA (mtDNA) sequencing (n=6). Genetic aetiologies included mitochondrial diseases (57%), Aicardi-Goutières syndrome (20%), and monogenic causes of dystonia and/or epilepsy (17%) mimicking Leigh syndrome. Radiological abnormalities included T2-hyperintense lesions (n=26) and lesions caused by calcium or manganese mineralization (n=9). Three clusters were identified: the pallidal, neostriatal, and striatal, plus the last including mtDNA defects in the oxidative phosphorylation system with prominent brain atrophy. Mitochondrial biomarkers showed poor sensitivity and specificity in children with mitochondrial disease, whereas interferon signature was observed in all patients with patients with Aicardi-Goutières syndrome., Interpretation: Combined whole-exome and mtDNA sequencing allowed the identification of several genetic conditions affecting basal ganglia metabolism. We propose a diagnostic algorithm which prioritizes early use of next-generation sequencing on the basis of three clusters of basal ganglia lesions., (© 2022 Mac Keith Press.)

Background and Aims: Biotin-thiamine-responsive basal ganglia disease (BTBGD) is an autosomal recessive disorder due to mutations in the SLC19A3-gene, typically seen in early childhood., Materials and Methods: We report a 49-year-old lady presenting with rapidly progressive cognitive impairment, seizures, hypersomnolence, ataxia, and generalized dystonia of 3 weeks duration. The magnetic resonance imaging (MRI) of the brain revealed T2-hyperintensities in the basal ganglia, thalamus, cortical, subcortical regions with striatal necrosis suggestive of BTBGD that was confirmed by genetic analysis. She was treated with thiamine and biotin following which there was significant clinical and MRI improvement., Conclusions: BTBGD requires a high index of suspicion in any patient presenting with unexplained rapidly progressive dementia. High doses of biotin and thiamine are the mainstay of the treatment to achieve a favorable outcome., Competing Interests: None

Background: Woodhouse-Sakati syndrome is a rare autosomal recessive disease with endocrine and neuroectodermal aberrations with heterogeneous phenotypes and disease course. The most common phenotypes of the disease are progressive sensorineural hearing loss and alopecia, mild-to-moderate mental retardation and hypogonadism. The disease results from mutations in the DCAF17 gene., Method: Here, we reported a large consanguineous pedigree with multiple affected individuals with Woodhouse-Sakati syndrome phenotypes. Laboratory tests confirmed the endocrine perturbance in affected individuals. To find out the underlying genetic change, whole-exome sequencing was carried out., Result: Analysis of the exome data identified a splicing-site deletion NM_025000.3:c.1423-1_1425delGACA in DCAF17 gene. Sanger sequencing confirmed the co-segregation of the variant with the disease phenotypes in the family., Conclusion: The variant is predicted to cause aberrant splicing, i.e., exon skipping, resulting in the translation of a truncated functionless protein which results in appearance of typical phenotypic features and clinical laboratory findings of Woodhouse-Sakati syndrome in affected members of the family., (© 2021 The Authors. Journal of Clinical Laboratory Analysis published by Wiley Periodicals LLC.)

Type-III sodium-dependent phosphate transporters 1 and 2 (PiT 1 and PiT 2, respectively) are proteins encoded by SLC20A1 and SLC20A2, respectively. The ubiquitous distribution of SLC20A1 and SLC20A2 mRNAs in mammalian tissues supports the housekeeping maintenance and homeostasis of intracellular inorganic phosphate (Pi), which is absorbed from interstitial fluid for normal cellular functions. SLC20A2 variants have been found in patients with idiopathic basal ganglia calcification (IBGC), also known as Fahr's disease or primary familial brain calcification (PFBC). Thus, disrupted Pi homeostasis is considered one of the major factors in the pathogenic mechanism of IBGC. In this paper, among the causative genes of IBGC, we focused specifically on PiT2, and its potential for a therapeutic target of IBGC., Competing Interests: Declaration of competing interest None., (Copyright © 2021 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

Woodhouse-Sakati syndrome (WSS) (OMIM#241080) is a rare multi-system autosomal recessive disease with homozygous mutation of the DCAF17 gene. The main features of WSS include diabetes, hypogonadism, alopecia, deafness, intellectual disability and progressive extrapyramidal syndrome. We identified a WSS family with a novel DCAF17 gene mutation type in China. Two unconsanguineous siblings from the Chinese Han family exhibiting signs and symptoms of Woodhouse-Sakati syndrome were presented for evaluation. Whole-exome sequencing revealed a homozygous deletion NM_025000.4:c.1488_1489delAG in the DCAF17 gene, which resulted in a frameshift mutation that led to stop codon formation. We found that the two patients exhibited low insulin and C-peptide release after glucose stimulation by insulin and C-peptide release tests. These findings indicate that the DCAF17 gene mutation may cause pancreatic β cell functional impairment and contribute to the development of diabetes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhou, Shi, Zheng, Chen, Wang, Xiao, Cui, Qiu, Zhu and Li.)

We conducted a review of hospital records of infants with acute encephalitis syndrome with bilateral symmetrical basal ganglia infarcts, between 2011-2015, at a single center in Assam. Thiamine (as part of multivitamin injection) was used in the treatment of 23 infants and not used in 27; Only 1 (3.7%) infant died in the former group and 20 infants (86.9%) died in the latter [RR (95% CI) 0.04 (0.006,0.29); P<0.001). Two infants on follow-up had normal development, both in the thiamine group. The study suggests the possibility of subclinical thiamine deficiency, mitochondrial diseases, or SLC19A3 gene mutation in this population.

CalDAG-GEFI (CDGI) is a protein highly enriched in the striatum, particularly in the principal spiny projection neurons (SPNs). CDGI is strongly down-regulated in two hyperkinetic conditions related to striatal dysfunction: Huntington's disease and levodopa-induced dyskinesia in Parkinson's disease. We demonstrate that genetic deletion of CDGI in mice disrupts dendritic, but not somatic, M1 muscarinic receptors (M1Rs) signaling in indirect pathway SPNs. Loss of CDGI reduced temporal integration of excitatory postsynaptic potentials at dendritic glutamatergic synapses and impaired the induction of activity-dependent long-term potentiation. CDGI deletion selectively increased psychostimulant-induced repetitive behaviors, disrupted sequence learning, and eliminated M1R blockade of cocaine self-administration. These findings place CDGI as a major, but previously unrecognized, mediator of cholinergic signaling in the striatum. The effects of CDGI deletion on the self-administration of drugs of abuse and its marked alterations in hyperkinetic extrapyramidal disorders highlight CDGI's therapeutic potential., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Idiopathic basal ganglia calcification (IBGC) is a rare neurodegenerative disease, characterized by abnormal calcium deposits in basal ganglia of the brain. The affected individuals exhibit movement disorders, and progressive deterioration of cognitive and psychiatric ability. The genetic cause of the disease is mutation in one of several different genes, SLC20A2, PDGFB, PDGFRB, XPR1 or MYORG, which inheritably or sporadically occurs. Here we generated an induced pluripotent stem cell (iPSC) line from an IBGC patient, which is likely be a powerful tool for revealing the pathomechanisms and exploring potential therapeutic candidates of IBGC., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Primary familial brain calcification (PFBC) is a rare inherited disease characterized by multiple calcified foci in the brain parenchyma. MYORG is the first gene found to be associated with autosomal recessive PFBC. The precise pathogenic mechanism of neurodegeneration in PFBC remains unclear. The clinical phenotypes of PFBC are variable, and there is no clear correlation between clinical manifestations and radiological and pathological features of calcification., Case Presentation: Two sisters in a Taiwanese family presented with young-onset Parkinsonism and multifocal dystonia. Their brain CTs showed multiple intracerebral calcifications. The genetic study detected two heterozygous novel variants, c.104 T > A (p.Met35Lys) and c.850 T > C (p.Cys284Arg) in the MYORG gene. In both patients, MR susceptibility weighted images revealed calcification of the deep medullary veins. Tc 99m ECD SPECT demonstrated a significant decrease of tracer uptake in the brain cortex and subcortical gray matter. Tc 99m TRODAT-1 SPECT revealed decreased tracer uptake in the bilateral striatum., Conclusion: Two novel MYORG variants were identified in Taiwanese family members presenting with PFBC. Abnormalities in the brain perfusion and dopamine transporter SPECTs suggest that cerebral ischemia due to extensive calcified vasculopathy, disruption of the basal ganglia-thalamo-cortical circuit, and nigrostriatal dopaminergic dysfunction are plausible pathogenic mechanisms of neurodegeneration in PFBC patients. Further investigation into the correlations between the pathogenicity-implicated imaging findings and the clinical phenotype are recommended.

We present the clinicopathological findings of a case of combined Fahr's disease (FD) and dementia with Lewy bodies (DLB), associated with a novel pathogenic mutation. The patient presented with visual hallucinations, fluctuating confusion and parkinsonism, leading to a presumptive diagnosis of DLB. CT scan showed extensive bilateral parenchymal calcifications, suggestive of FD. DNA sequencing identified a novel missense variant (c.92A>T p.(Asn31Ile)) in the SLC20A2 gene, a gene known to be associated with FD. This change has not been previously recorded in genetic repositories, and in silico analyses classified it as likely to be disease-causing. The patient died aged 77, four years after symptom onset. Neuropathological examination revealed, macroscopically and microscopically, extensive calcification in the striatum, globus and cerebellar white matter. There was also neuronal loss in the substantia nigra and residual neurones contained alpha-synuclein-positive Lewy bodies. The neuropathology was therefore consistent with DLB and FD. A literature review identified 3 other cases of co-existing Fahr's and Lewy body pathology, thus the frequency of dual pathology (44%) is higher than expected by random association. Further studies are needed to determine whether alpha-synucleinopathy is linked mechanistically to FD and/or represents a phenotypic subtype.

Aim: To present seven new genetically confirmed cases of biotin-thiamin-responsive basal ganglia disease (BTBGD) with different clinical and brain magnetic resonance imaging (MRI) characteristics., Material and Methods: Genetic variants, clinical presentations, brain MRI findings, treatment response, and prognosis of seven selected patients with BTBGD, diagnosed with SLC19A3 mutations were described., Results: Among seven patients diagnosed with BTBGD, two had early infantile form, four had classic childhood form, and one was asymptomatic. Four different homozygous variants were found in the SLC19A3. Two patients with early infantile form presented with encephalopathy, dystonia, and refractory seizure in the neonatal period and have different variants. Their MRI findings were similar and pathognomonic for the early infantile form. Three siblings had same variants: one presented seizure and encephalopathy at the age of 4 months, one presented seizure at 14 years, and another was asymptomatic at 20 years. Only one of them had normal MRI findings, and the others MRI findings were similar and suggestive of the classic form. Other two siblings; one of them presented with developmental delay, seizure, and dystonia at 18 months and the other presented with subacute encephalopathy and ataxia at 20 months. Their MRI findings were also similar and suggestive of the classic form., Conclusion: BTBGD may present with dissimilar clinical characteristics or remain asymptomatic for a long time period even in a family or patients with same variants. Brain MRI patterns may be important for the early diagnosis of BTBGD that would save children's lives., (Copyright © 2020 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.)

Objective: The authors examined the effects of two common functional polymorphisms-brain-derived neurotrophic factor (BDNF) Val66Met and catechol- O -methyltransferase (COMT) Val158Met-on cognitive, neuropsychiatric, and motor symptoms and MRI findings in persons with frontotemporal lobar degeneration (FTLD) syndromes., Methods: The BDNF Val66Met and COMT Val158Met polymorphisms were genotyped in 174 participants with FTLD syndromes, including behavioral variant frontotemporal dementia, primary progressive aphasia, and corticobasal syndrome. Gray matter volumes and scores on the Delis-Kaplan Executive Function System, Mattis Dementia Rating Scale, Wechsler Memory Scale, and Neuropsychiatric Inventory were compared between allele groups., Results: The BDNF Met allele at position 66 was associated with a decrease in depressive symptoms (F=9.50, df=1, 136, p=0.002). The COMT Val allele at position 158 was associated with impairment of executive function (F=6.14, df=1, 76, p=0.015) and decreased bilateral volume of the head of the caudate in patients with FTLD (uncorrected voxel-level threshold of p<0.001). Neither polymorphism had a significant effect on motor function., Conclusions: These findings suggest that common functional polymorphisms likely contribute to the phenotypic variability seen in patients with FTLD syndromes. This is the first study to implicate BDNF polymorphisms in depressive symptoms in FTLD. These results also support an association between COMT polymorphisms and degeneration patterns and cognition in FTLD.

Introduction: We explore the transcription factors involved in the molecular mechanism of antipsychotic (AP)-induced acute extrapyramidalsymptoms (EPS) in order to identify new candidate genes for pharmacogenetic studies., Methods: Protein-protein interaction (PPI) networks previously created from three pharmacogenomic models (in vitro, animal, and peripheral blood inhumans) were used to, by means of several bioinformatic tools; identify key transcription factors (TFs) that regulate each network. Once the TFs wereidentified, SNPs disrupting the binding sites (TFBS) of these TFs in the genes of each network were selected for genotyping. Finally, SNP-basedassociations with EPS were analyzed in a sample of 356 psychiatric patients receiving AP., Results: Our analysis identified 33 TFs expressed in the striatum, and 125 SNPs disrupting TFBS in 50 genes of our initial networks. Two SNPs (rs938112,rs2987902) in two genes (LSMAP and ABL1) were significantly associated with AP induced EPS (p < 0.001). These SNPs disrupt TFBS regulated byPOU2F1., Conclusion: Our results highlight the possible role of the disruption of TFBS by SNPs in the pharmacological response to AP.

Competing Interests: Declaration of competing interest No conflict of interest.

Beta-propeller protein-associated neurodegeneration (BPAN) is categorized in Neurodegeneration with brain iron accumulation. The clinical feature of BPAN is global developmental delay in early childhood, followed rapid progression of cognitive disfunction and parkinsonism in adulthood. This case was pointed out intellectual disability at the age of 9, followed left dominant progressive parkinsonism from the age of 31. Brain MRI showed the T 1 -weighted signal hyperintensity of the substantia nigra with a central band of hypointensity and the T 2 star weighted image hypointensity of substantia nigra and globus pallidus presenting dominant at right side. DAT SPECT also showed specific binding ratio decreased dominant in right side. She was diagnosed BPAN based on her genetic test revealing a novel mutation (c.411dupT) in WDR45. No studies reported detailed parkinsonism like laterality in BPAN. This case indicates the left dominant parkinsonism was caused by right dominant iron deposition to substantia nigra and globus pallidus in view of MRI findings and DAT SPECT.

Background: Woodhouse-Sakati syndrome (WSS) is a rare neuroendocrine and ectodermal disorder inherited in an autosomal recessive pattern. The syndrome presents prominent clinical features, including alopecia, neuroendocrine defects, neurological findings and progressive hearing loss. The condition results from mutations in the DCAF17 gene., Aims: To search for the underlying genetic defect in a Pakistani family with WSS phenotypes., Methodology: Whole exome sequencing was used to search for the disease-causing variant., Results: Analysis of the exome data revealed a start loss sequence variant (c.1A>G, p.M1?) in DCAF17., Conclusion: This variant is predicted to abolish translation of the DCAF17 polypeptide. To our knowledge, this is the first start loss variant identified in the DCAF17., (© 2019 British Association of Dermatologists.)

Objective: To explore the genetic basis for a neonate featuring global developmental delay., Methods: Clinical and laboratory tests were carried out for the patient. Peripheral venous blood samples were collected from the neonate and his parents for the extraction of DNA. Potential variant was detected by using targeted capture and next generation sequencing for a panel of genes associated with nervous system diseases. Suspected variant was validated by Sanger sequencing., Results: The nine-month-old boy manifested global developmental delay and was unstable to sit alone and distinguish strangers from acquaintance. Genetic testing revealed two novel variants of the SLC19A3 gene in him, namely c.448G>A and c.169C>T. The amino acids encoded by the two codons are highly conservative, and both variants were predicted to be pathogenic by bioinformatic analysis., Conclusion: The compound heterozygous c.448G>A and c.169C>T variants probably underlay the onset of disease in the patient. Above finding also enriched the variant spectrum of SLC19A3 gene underlying Biotin-thiamine responsive basal ganglia disease.

Idiopathic basal ganglia calcification (IBGC), also known as Fahr disease, is a rare neurodegenerative disorder characterized by the accumulation of extensive parenchymal and vascular calcifications in the basal ganglia, with variable calcifications elsewhere in the brain. Typically, IBGC presents with neurologic and psychiatric symptoms in middle-aged adults. Recent genetic studies have identified alterations in 4 genes causing IBGC, including alterations in SLC20A2 on chromosome 8p11.2. Currently, there are no clinical descriptions of patients with IBGC occurring within the context of a complex genetic syndrome. Here, we present a case of pediatric 8p11 deletion with IBGC, hereditary spherocytosis, vitreoretinopathy, and focal cortical dysplasia. We review multiple cases of IBGC with pediatric onset due to SLC20A2 deletion in the literature, and raise the consideration of IBGC in the evaluation of pediatric patients with 8p11.2 deletion syndromes., (© 2020 American Association of Neuropathologists, Inc. All rights reserved.)

The product of thiamine phosphokinase is the cofactor for many enzymes, including the dehydrogenases of pyruvate, 2-ketoglutarate and branched chain ketoacids. Its deficiency has recently been described in a small number of patients, some of whom had a Leigh syndrome phenotype. The patient who also had a Leigh phenotype was initially found to have a low concentration of biotin in plasma and massive urinary excretion of biotin. Despite treatment with biotin and thiamine, her disease was progressive. Mutations c.311delG and c.426G > C were found in the TPK1 gene., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Adult genetic disorders causing brain lesions have been mostly described as white matter vanishing diseases. We present here the investigations realized in patients referred for psychiatric disorder with magnetic resonance imaging showing atypical basal ganglia lesions. Genetic explorations of this family revealed a new hereditary disease linked to glutathione metabolism., (© 2019 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.)

Background Woodhouse-Sakati syndrome (WSS) (OMIM#241080) is an extremely rare multisystemic disease. Alopecia, hypogonadism, loss of hearing, hypothyroidism, diabetes mellitus (DM) and neurological disorders are the components of this syndrome. The syndrome is caused by homozygous or compound heterozygous mutations in DCAF17, and has recently been implicated in the development of both male and female gonads, thus resulting in hypogonadism. Case report A 16-year-old girl with consanguineous parents was admitted to our hospital with absence of breast development and amenorrhea. Hypogonadism was detected, in the form of hypergonadotropic hypogonadism. Whole-exome sequencing was used to identify the genetic etiology underlying the hypogonadism. A novel homozygous variant c.1091 + 1G > A was detected in DCAF17. Both parents were sequenced and identified as heterozygous for the same mutation. Conclusions We report a novel mutation detected in the DCAF17 gene and discuss the clinical findings in patients with previously reported mutations. Various manifestations of WSS, such as alopecia, endocrinological and neurological disorders, do not emerge until later in life, and therefore this situation can be challenging to diagnose particularly in pediatric cases, as in the present report. Careful attention should be paid to these additional findings, which may lead to early diagnosis and reduced genetic analysis costs, in patients with hypogonadism. In addition, there was no obvious genetic-phenotype correlation in reported cases.

Idiopathic basal ganglia calcification (IBGC) is a rare intractable disease characterized by abnormal mineral deposits, including mostly calcium in the basal ganglia, thalamus, and cerebellum. SLC20A2 is encoding the phosphate transporter PiT-2 and was identified in 2012 as the causative gene of familial IBGC. In this study, we investigated functionally two novel SLC20A2 variants (c.680C > T, c.1487G > A) and two SLC20A2 variants (c.82G > A, c.358G > C) previously reported from patients with IBGC. We evaluated the function of variant PiT-2 using stable cell lines. While inorganic phosphate (Pi) transport activity was abolished in the cells with c.82G > A, c.358G > C, and c.1487G > A variants, activity was maintained at 27.8% of the reference level in cells with the c.680C > T variant. Surprisingly, the c.680C > T variant had been discovered by chance in healthy members of an IBGC family, suggesting that partial preservation of Pi transport activity may avoid the onset of IBGC. In addition, we confirmed that PiT-2 variants could be translocated into the cell membrane to the same extent as PiT-2 wild type. In conclusion, we investigated the PiT-2 dysfunction of four SLC20A2 variants and suggested that a partial reduced Pi transport function of PiT-2 might not be sufficient to induce brain calcification of IBGC.

Woodhouse-Sakati Syndrome is a very rare autosomal recessive disorder caused by pathogenic variants in the DCAF17 gene, which encodes DDB1- and CUL4-associated factor 17. It is a multisystemic disorder characterized by hypogonadism, adolescent- to young adult-onset diabetes mellitus, hypothyroidism, and alopecia. Neurologic involvement includes childhood-onset moderate bilateral sensorineural hearing loss, mild intellectual disability adolescent- to young adult-onset of extrapyramidal findings, dysarthria, and dysphagia. Brain imaging typically reveals iron deposition in the globus pallidus and periventricular leukodystrophy. We report the case of a 31-year-old Portuguese female, the only child of a consanguineous couple. She presented with cognitive impairment, spastic paraparesis, lower limb dystonia, dysarthria, and dysphagia. She also had hypergonadotrophic hypogonadism associated with primary amenorrhea, insulin-dependent diabetes mellitus with retinopathy, primary hypothyroidism, moderate bilateral sensorineural hearing loss, and alopecia. Serial brain magnetic resonance imaging showed a progressive periventricular leukodystrophy with pontine involvement and significant bilateral iron deposition in the globus pallidus, substantia nigra, and red nucleus. The diagnosis of Woodhouse-Sakati Syndrome was eventually proposed and DCAF17 gene sequencing identified a novel likely pathogenic homozygous variant NG&#95;013038.1(NM&#95;025000.3):c.1091+2T>C. Genetic testing allowed a more accurate prognosis and a precise genetic counseling for our patient's family., (© 2019 Wiley Periodicals, Inc.)

Microsatellite repeat expansion disease loci can exhibit pleiotropic clinical and biological effects depending on repeat length. Large expansions in C9orf72 (100s-1000s of units) are the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal degeneration (FTD). However, whether intermediate expansions also contribute to neurodegenerative disease is not well understood. Several studies have identified intermediate repeats in Parkinson's disease patients, but the association was not found in autopsy-confirmed cases. We hypothesized that intermediate C9orf72 repeats are a genetic risk factor for corticobasal degeneration (CBD), a neurodegenerative disease that can be clinically similar to Parkinson's but has distinct tau protein pathology. Indeed, intermediate C9orf72 repeats were significantly enriched in autopsy-proven CBD (n = 354 cases, odds ratio = 3.59, p = 0.00024). While large C9orf72 repeat expansions are known to decrease C9orf72 expression, intermediate C9orf72 repeats result in increased C9orf72 expression in human brain tissue and CRISPR/cas9 knockin iPSC-derived neural progenitor cells. In contrast to cases of FTD/ALS with large C9orf72 expansions, CBD with intermediate C9orf72 repeats was not associated with pathologic RNA foci or dipeptide repeat protein aggregates. Knock-in cells with intermediate repeats exhibit numerous changes in gene expression pathways relating to vesicle trafficking and autophagy. Additionally, overexpression of C9orf72 without the repeat expansion leads to defects in autophagy under nutrient starvation conditions. These results raise the possibility that therapeutic strategies to reduce C9orf72 expression may be beneficial for the treatment of CBD.

Basal ganglia calcifications could be incidental findings up to 20% of asymptomatic patients undergoing CT or MRI scan. The presence of neuropsychiatric symptoms associated with bilateral basal ganglia calcifications (which could occur in other peculiar brain structures, such as dentate nuclei) identifies a clinical picture defined as Fahr's Disease. This denomination mainly refers to idiopathic forms in which no metabolic or other underlying causes are identified. Recently, mutations in four different genes (SLC20A2, PDGFRB, PDGFB, and XPR1) were identified, together with novel mutations in the Myogenic Regulating Glycosylase gene, causing the occurrence of movement disorders, cognitive decline, and psychiatric symptoms. On the other hand, secondary forms, also identified as Fahr's syndrome, have been associated with different conditions: endocrine abnormalities of PTH, such as hypoparathyroidism, other genetically determined conditions, brain infections, or toxic exposure. The underlying pathophysiology seems to be related to an abnormal calcium/phosphorus homeostasis and transportation and alteration of the blood-brain barrier.

Background: Biotin-thiamine-responsive basal ganglia disease (BTBGD) is an autosomal recessive neurometabolic disorder mostly presented in children. The disorder is described as having subacute encephalopathy with confusion, dystonia, and dysarthria triggered by febrile illness that leads to neuroregression and death if untreated. Using biotin and thiamine at an early stage of the disease can lead to significant improvement., Methods: BTBGD is a treatable disease if diagnosed at an early age and has been frequently reported in Saudi population. Keeping this in mind, the current study screened 3000 Saudi newborns for the SLC19A3 gene mutations using target sequencing, aiming to determine the carrier frequency in Saudi Population and whether BTBGD is a good candidate to be included in the newborn-screened disorders., Results: Using targeted gene sequencing, DNA from 3000 newborns Saudi was screened for the SLC19A3 gene mutations using standard methods. Screening of the SLC19A3 gene revealed a previously reported heterozygous missense mutation (c.1264A>G (p.Thr422Ala) in six unrelated newborns. No probands having homozygous pathogenic mutations were found in the studied cohort. The variant has been frequently reported previously in homozygous state in Saudi population, making it a hot spot mutation. The current study showed that the carrier frequency of SLC19A3 gene mutation is 1 of 500 in Saudi newborns., Conclusion: For the first time in the literature, we determined the carrier frequency of SLC19A3 gene mutation in Saudi population. The estimated prevalence is too rare in Saudi population (at least one in million); therefore, the data are not in favor of including such very rare disorders in newborn screening program at population level. However, a larger cohort is needed for a more accurate estimate., (© 2019 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.)

Competing Interests: Each author has no conflicts of interests to declare.

Background and Purpose: The recent advances in genetics have helped to unravel the cause of many dystonia syndromes. With the broadening spectrum of genetically defined dystonia syndromes, distinct clinico-radiological phenotypes are a welcome handle to guide the diagnostic work-up., Methods: Exome sequencing was used to elucidate the genetic cause of a syndrome characterized by generalized dystonia, pyramidal and cerebellar involvement, with bilateral striatal necrosis (BSN) and cerebellar atrophy on magnetic resonance imaging. Homozygosity mapping and linkage analysis were used in a supportive role. Known genetic causes of BSN were excluded by use of exome data or Sanger sequencing., Results: Compound heterozygous mutations were identified in the NUBPL gene in a small UK kindred. The gene lay in a region of positive linkage and segregated with disease in a family of six individuals., Conclusion: NUBPL mutations cause early onset, autosomal recessive generalized dystonia with cerebellar ataxia, pyramidal signs, preserved cognition and a distinct magnetic resonance imaging appearance with BSN and cerebellar atrophy., (© 2019 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)

Introduction: Spinocerebellar ataxia 48 has recently been described as an adult onset ataxia associated with a cerebellar cognitive affective syndrome, caused by a heterozygous mutation in the STUB1 gene., Methods: We characterized the clinical and neuroimaging phenotype of eight patients from two autosomal dominant ataxia multigenerational Italian families, in whom we conducted whole exome sequencing, targeted multigene sequencing, and Sanger sequencing studies., Results: We describe a complex syndrome characterized by ataxia and cognitive-psychiatric disorder in all cases, variably associated with chorea, parkinsonism, dystonia, urinary symptoms, and epilepsy. MRI showed a significant cerebellar atrophy, coupled to a T2-weighted hyperintensity affecting the dentate nuclei and extending to the middle cerebellar peduncles, whereas FDG-PET studies revealed glucose hypometabolism in cerebellum, striatum, and cerebral cortex. We identified two different novel STUB1 mutations segregating in the two families. One of the two mutations, p.(Gly33Ser), occurs in the TRP domain, whereas p.(Pro228Ser) is located in the ubiquitin ligase region., Discussion: We emphasize the similarity of the described clinical picture with that of SCAR16, an autosomal recessive ataxia caused by biallelic mutations in the same gene, and of spinocerebellar ataxia type 17, which is considered the main Huntington's disease-like syndrome. The pathogenesis of the disease and the relationship between SCA48 and SCAR16 remain to be clarified., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Primary familial brain calcification (PFBC) is a rare neurological disorder. Mutations in five genes (SLC20A2, PDGFRB, PDGFB, XPR1, and MYORG) have been linked to PFBC. Here, we used SYBR green-based real-time quantitative polymerase chain reaction (PCR) assay and denaturing high-performance liquid chromatography analysis to detect copy number variants (CNVs) in 20 unrelated patients with PFBC, negatively sequenced for the five known genes. We identified three deletions in SLC20A2, including a large de novo full gene deletion and two exonic deletions confined to exon 2 and exon 6, respectively. Subsequent linked-read whole-genome sequencing of the patient with the large deletion showed a 1.7 Mb heterozygous deletion which removed the entire coding regions of SLC20A2 as well as 21 other genes. In the family with a deletion of exon 6, a missense variant of uncertain significance (SLC20A2: p.E267Q) also co-segregated with the disease. Functional assay showed the deletion could result in significantly impaired phosphate transport, whereas the p.E267Q variant did not. Our results confirm that deletion in SLC20A2 is a causal mechanism for PFBC and highlight the importance of functional study for classifying a rare missense variant as (likely) pathogenic., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)