Early rise in brain damage markers and high ICOS expression in CD4+ and CD8+ T cells during checkpoint inhibitor-induced encephalomyelitis.

We report a case of rapid eradication of melanoma brain metastases and simultaneous near-fatal encephalomyelitis following double immune checkpoint blockade. Brain damage marker S-100B and C reactive protein increased before symptoms or signs of encephalomyelitis and peaked when the patient fell into a coma. At that point, additional brain damage markers and peripheral T cell phenotype was analyzed. The analyses were repeated four times during the patient's recovery. Axonal damage marker neurofilament light polypeptide (NFL) and astrocytic damage marker glial fibrillar acidic protein (GFAP) were very high in blood and cerebrospinal fluid and gradually normalized after immunosuppression and intensive care. The costimulatory receptor inducible T cell costimulatory receptor (ICOS) was expressed on a high proportion of CD4+ and CD8+T cells as encephalomyelitis symptoms peaked and then gradually decreased in parallel with clinical improvement. Both single and double immune checkpoint inhibitor-treated melanoma patients with other serious immune-related adverse events (irAE) (n=9) also expressed ICOS on a significantly higher proportion of CD4+ and CD8+T cells compared with controls without irAE (n=12). In conclusion, our results suggest a potential role for ICOS on CD4+ and CD8+T cells in mediating encephalomyelitis and other serious irAE. In addition, brain damage markers in blood could facilitate early diagnosis of encephalitis.

RAB7L1 Participates in Secondary Brain Injury Induced by Experimental Intracerebral Hemorrhage in Rats.

RAB7, a member of RAS oncogene family-like 1 (RAB7L1), is a GTPase belonging to the Rab family and acts as an upstream regulator to regulate the kinase activity of leucine-rich repeat kinase 2 (LRRK2). Although LRRK2 has been shown to aggravate secondary brain injury (SBI) after intracerebral hemorrhage (ICH), it is unknown whether RAB7L1 is also involved in this process. The purpose of the present study was to investigate the role of RAB7L1 in ICH-induced SBI in vivo. Autologous blood was injected into adult male Sprague-Dawley rats to induce an ICH model in vivo. The results showed that the protein levels of RAB7L1 increased after ICH. Overexpression of RAB7L1 induced neuronal apoptosis and damage, as demonstrated by TUNEL-positive and FJB-positive cells, and exacerbated ICH-induced learning and cognitive dysfunctions; in contrast, downregulation of RAB7L1 via RNA interference yielded comparatively opposite changes in these parameters. In summary, this study demonstrates that RAB7L1 promotes SBI after ICH and may represent a potential target for ICH therapy.

MicroRNA-130a regulates neurological deficit and angiogenesis in rats with ischaemic stroke by targeting XIAP.

MicroRNAs (miRNAs) have already been proposed to be implicated in the development of ischaemic stroke. We aim to investigate the role of miR-130a in the neurological deficit and angiogenesis in rats with ischaemic stroke by regulating X-linked inhibitor of apoptosis protein (XIAP). Middle cerebral artery occlusion (MCAO) models were established by suture-occluded method, and MCAO rats were then treated with miR-130a mimics/inhibitors or/and altered XIAP for detection of changes of rats' neurological function, nerve damage and angiogenesis in MCAO rats. The oxygen-glucose deprivation (OGD) cellular models were established and respectively treated to determine the roles of miR-130a and XIAP in neuronal viability and apoptosis. The expression levels of miR-130a and XIAP in brain tissues of MCAO rats and OGD-treated neurons were detected. The binding site between miR-130a and XIAP was verified by luciferase activity assay. MiR-130a was overexpressed while XIAP was down-regulated in MCAO rats and OGD-treated neurons. In animal models, suppressed miR-130a improved neurological function, alleviated nerve damage and increased new vessels in brain tissues of rats with MCAO. In cellular models, miR-130a inhibition promoted neuronal viability and suppressed apoptosis. Inhibited XIAP reversed the effect of inhibited miR-130a in both MCAO rats and OGD-treated neurons. XIAP was identified as a target of miR-130a. Our study reveals that miR-130a regulates neurological deficit and angiogenesis in rats with MCAO by targeting XIAP.

Joint Effects of GWAS SNPs in Coagulation System Confer Risk to Hypertensive Intracerebral Hemorrhage.

Recent genome-wide association studies (GWAS) have identified numerous single nucleotide polymorphisms (SNPs) associated with coagulation system, including hemostatic factors and hematological phenotypes. However, few articles described the relationships between these SNPs and the risk of hemorrhagic stroke. The aim of our study was to evaluate the roles of these SNPs as risk factors and survival predictors for hemorrhagic stroke. Thirteen SNPs from GWAS in coagulation system were genotyped in a Chinese Han population including 1000 patients with hemorrhagic stroke (intracerebral hemorrhage, ICH = 743; subarachnoid hemorrhage, SAH = 257) and 1044 population-based controls. The associations between the genetics risk score (GRS) and risk of hemorrhagic stroke as well as post-stroke adverse outcomes were determined. No individual SNP was associated with the risk of hemorrhagic stroke. The GRS was calculated by summing the number of risk alleles of each SNP, and a total of 13 SNPs were included. Meanwhile, the GRS cutoffs values were defined to be close to quartiles or tertiles in control subjects. For quartiles, individuals with GRS about 8-9, 10-11, ≥12 had 1.28 (OR 1.28, 95% CI 0.98-1.68, p = 0.067)-, 1.36 (OR 1.36, 95% CI 1.04-1.79, p = 0.026)-, 1.53 (OR 1.53, 95% CI 1.13-2.07, p = 0.006)-fold increase in ICH risk compared to those with GRS ≤7, respectively; for tertiles, individuals with GRS about GRS 9-10, ≥11 had 0.98 (OR 0.98, 95% CI 0.78-1.23, p = 0.067)- and 1.26 (OR 1.26, 95% CI 1.00-1.59, p = 0.048)-fold increase in ICH risk compared to those with GRS ≤8, respectively. Further stratification analyses indicated that this association was only found in hypertensive ICH subjects. However, no statistical difference was found in the volume of hematoma, activities of daily living scale as well as hospital death in the ICH patients based on GRS values. Joint effects of SNPs associated with low coagulation factor levels might confer risk to ICH patients with hypertension. However, the clinical value on risk stratification and survival prediction was limited.

Hematopoietic Stem Cell Gene Therapy for Storage Disease: Current and New Indications.

Lysosomal storage disorders (LSDs) are a broad class of monogenic diseases with an overall incidence of 1:7,000 newborns, due to the defective activity of one or more lysosomal hydrolases or related proteins resulting in storage of un-degraded substrates in the lysosomes. The over 40 different known LSDs share a life-threatening nature, but they are present with extremely variable clinical manifestations, determined by the characteristics and tissue distribution of the material accumulating due to the lysosomal dysfunction. The majority of LSDs lack a curative treatment. This is particularly true for LSDs severely affecting the CNS. Based on current preclinical and clinical evidences, among other treatment modalities, hematopoietic stem cell gene therapy could potentially result in robust therapeutic benefit for LSD patients, with particular indication for those characterized by severe brain damage. Optimization of current approaches and technology, as well as implementation of clinical trials for novel indications, and prolonged and more extensive follow-up of the already treated patients will allow translating this promise into new medicinal products.

Is APOE ε4 associated with poorer cognitive outcome following traumatic brain injury? A meta-analysis.

OBJECTIVE: Cognitive impairment is a common sequelae of traumatic brain injury (TBI); however, predicting who will experience poorer outcomes remains challenging. A potential risk factor that has gained attention is the APOE gene, with the ε4 allele hypothesized to have a detrimental effect on post-TBI cognitive outcome. The aim of this meta-analysis was to evaluate the effect of APOE ε4 both in terms of general cognitive function and within specific domains known to be prone to impairment following TBI (executive function, working memory, verbal memory and visual memory). METHOD: A literature search was undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA), resulting in the inclusion of 10 studies (ε4-carriers n = 143, noncarriers n = 510). Neuropsychological tasks were identified, and Cohen's d was calculated and pooled. Meta-analyses were conducted on general cognitive functioning and for the specific cognitive domains of interest. RESULTS: No significant differences were found between APOE ε4-carriers or noncarriers, either in general cognitive function or in the cognitive domains of executive function, working memory, verbal memory, or visual memory. CONCLUSIONS: This meta-analysis indicates that APOE ε4 does not have a detrimental effect on cognitive performance following TBI. We propose that the relationship between APOE and cognitive function following TBI is complex, and a more-nuanced exploration of APOE genotypes is needed. (PsycINFO Database Record

[Intracranial aneurysms and their clinical and genetic behaviour]. / Aneurismas intracraneales y su comportamiento clínico-genético.

BACKGROUND: Intracranial aneurysms are abnormal dilations of the cerebral arteries of unknown origin. However, some genes have been linked to their formation, as in the case of NOS3 gene which encodes the endothelial nitric oxide synthase responsible for producing nitric oxide. Several polymorphisms in this gene, in association with a variable number tandem repeat located in intron 4 from eNOS4 gene, can influence the formation of aneurysms. Therefore, the purpose of this study is to determine the genotype frequencies of eNOS3 and eNOS4 genes, and their relationship with intracranial aneurysms. MATERIAL AND METHODS: A prospective case-control study was performed on 79 cases with ruptured intracranial aneurysm and 93 healthy controls. DNA was obtained from all subjects for the study of the eNOS3 and eNOS4 genes by molecular techniques. RESULTS: The GG genotype of eNOS3 gene showed the largest number of patients (n=29) with a large aneurysm. While the intracranial aneurysms of medium size were found in a higher percentage (50%) in patients with genotype GT. In terms of patient outcomes, it was observed that those with genotype GG had the highest percentage (43.13%) recovery, compared to genotype GT (27.27%). CONCLUSIONS: The present study shows that there is a tendency of an association between genotypes of eNOS3 gene with the mean size of the aneurysm, as well as clinical sequelae of the disease in patients with intracranial aneurysms.

Association of NOS3 gene variants and clinical contributors of hypoxic-ischemic encephalopathy

The aim of this study was to analyze the association of different clinical contributors of hypoxic-ischemic encephalopathy with NOS3 gene polymorphisms. A total of 110 children with hypoxic-ischemic encephalopathy and 128 control children were selected for this study. Association of gender, gestational age, birth weight, Apgar score, cranial ultrasonography, and magnetic resonance imaging findings with genotypic data of six haplotype-tagging single nucleotide polymorphisms and the most commonly investigated rs1800779 and rs2070744 polymorphisms was analyzed. The TGT haplotype of rs1800783, rs1800779, and rs2070744 polymorphisms was associated with hypoxic-ischemic encephalopathy. Children with the TGT haplotype were infants below 32 weeks of gestation and they had the most severe brain damage. Increased incidence of the TT genotype of the NOS3 rs1808593 SNP was found in the group of hypoxic-ischemic encephalopathy patients with medium and severe brain damage. The probability of brain damage was twice as high in children with the TT genotype than in children with the TG genotype of the same polymorphism. Furthermore, the T allele of the same polymorphism was twice as frequent in children with lower Apgar scores. This study strongly suggests associations of NOS3 gene polymorphism with intensity of brain damage and severity of the clinical picture in affected children.

Mutations of the thyroid hormone transporter MCT8 cause prenatal brain damage and persistent hypomyelination.

CONTEXT: Mutations in the MCT8 (SLC16A2) gene, encoding a specific thyroid hormone transporter, cause an X-linked disease with profound psychomotor retardation, neurological impairment, and abnormal serum thyroid hormone levels. The nature of the central nervous system damage is unknown. OBJECTIVE: The objective of the study was to define the neuropathology of the syndrome by analyzing brain tissue sections from MCT8-deficient subjects. DESIGN: We analyzed brain sections from a 30th gestational week male fetus and an 11-year-old boy and as controls, brain tissue from a 30th and 28th gestational week male and female fetuses, respectively, and a 10-year-old girl and a 12-year-old boy. METHODS: Staining with hematoxylin-eosin and immunostaining for myelin basic protein, 70-kDa neurofilament, parvalbumin, calbindin-D28k, and synaptophysin were performed. Thyroid hormone determinations and quantitative PCR for deiodinases were also performed. RESULTS: The MCT8-deficient fetus showed a delay in cortical and cerebellar development and myelination, loss of parvalbumin expression, abnormal calbindin-D28k content, impaired axonal maturation, and diminished biochemical differentiation of Purkinje cells. The 11-year-old boy showed altered cerebellar structure, deficient myelination, deficient synaptophysin and parvalbumin expression, and abnormal calbindin-D28k expression. The MCT8-deficient fetal cerebral cortex showed 50% reduction of thyroid hormones and increased type 2 deiodinase and decreased type 3 deiodinase mRNAs. CONCLUSIONS: The following conclusions were reached: 1) brain damage in MCT8 deficiency is diffuse, without evidence of focal lesions, and present from fetal stages despite apparent normality at birth; 2) deficient hypomyelination persists up to 11 years of age; and 3) the findings are compatible with the deficient action of thyroid hormones in the developing brain caused by impaired transport to the target neural cells.

Association of NOS3 gene variants and clinical contributors of hypoxic-ischemic encephalopathy.

The aim of this study was to analyze the association of different clinical contributors of hypoxic-ischemic encephalopathy with NOS3 gene polymorphisms. A total of 110 children with hypoxic-ischemic encephalopathy and 128 control children were selected for this study. Association of gender, gestational age, birth weight, Apgar score, cranial ultrasonography, and magnetic resonance imaging findings with genotypic data of six haplotype-tagging single nucleotide polymorphisms and the most commonly investigated rs1800779 and rs2070744 polymorphisms was analyzed. The TGT haplotype of rs1800783, rs1800779, and rs2070744 polymorphisms was associated with hypoxic-ischemic encephalopathy. Children with the TGT haplotype were infants below 32 weeks of gestation and they had the most severe brain damage. Increased incidence of the TT genotype of the NOS3 rs1808593 SNP was found in the group of hypoxic-ischemic encephalopathy patients with medium and severe brain damage. The probability of brain damage was twice as high in children with the TT genotype than in children with the TG genotype of the same polymorphism. Furthermore, the T allele of the same polymorphism was twice as frequent in children with lower Apgar scores. This study strongly suggests associations of NOS3 gene polymorphism with intensity of brain damage and severity of the clinical picture in affected children.

Dravet syndrome--from epileptic encephalopathy to channelopathy.

Mutations in the gene encoding the α1 subunit of the voltage gated sodium channel (SCN1A) are associated with several epilepsy syndromes, ranging from relatively mild phenotypes found in families with genetic epilepsy with febrile seizures plus (GEFS+) to the severe infant-onset epilepsy Dravet syndrome. Evidence has emerged of the consequences of SCN1α dysfunction in different neuronal networks across the brain pointing toward a channelopathy model causing the neurologic features of Dravet syndrome that is beyond purely seizure related damage. A genetic change will present according to its severity, the genetic background of the individual, and environmental factors, and will affect a variety of neuronal networks according to channel distribution. This already-vulnerable system may be susceptible to secondary aggravating events such as status epilepticus. The channelopathy model implies that pharmacologic treatment and the restoration of impaired γ-aminobutyric acid (GABA)ergic neurotransmission might not only help prevent seizures but might affect the comorbidities of the syndrome. This critical review explores recent evidence relating to the pathogenicity of SCN1A mutations in Dravet syndrome and the effect these have on the wider disease phenotype and discusses whether knowledge of specific genotypes can influence clinical practice. Genetic technology is currently advancing at unprecedented speed and will increase our knowledge of new genes and interacting genetic networks. Clinicians and geneticists will have to work in close collaboration to guarantee good delivery and counseling of genetic testing results.

Common genetic variants and risk of brain injury after preterm birth.

BACKGROUND: The role of heritable factors in determining the common neurologic deficits seen after preterm birth is unknown, but the characteristic phenotype of neurocognitive, neuroanatomical, and growth abnormalities allows principled selection of candidate genes to test the hypothesis that common genetic variation modulates the risk for brain injury. METHODS: We collected an MRI-linked genomic DNA library from 83 preterm infants and genotyped tag single nucleotide polymorphisms in 13 relevant candidate genes. We used tract-based spatial statistics and deformation-based morphometry to examine the risks conferred by carriage of particular alleles at tag single nucleotide polymorphisms in a restricted number of genes and related these to the preterm cerebral endophenotype. RESULTS: Carriage of the minor allele at rs2518824 in the armadillo repeat gene deleted in velocardiofacial syndrome (ARVCF) gene, which has been linked to neuronal migration and schizophrenia, and rs174576 in the fatty acid desaturase 2 gene, which encodes a rate-limiting enzyme for endogenous long chain polyunsaturated fatty acid synthesis and has been linked to intelligence, was associated with white matter abnormality measured in vivo using diffusion tensor imaging (P = .0009 and P = .0019, respectively). CONCLUSIONS: These results suggest that genetic variants modulate white matter injury after preterm birth, and known susceptibilities to neurologic status in later life may be exposed by the stress of premature exposure to the extrauterine environment.

Oct-2 transcription factor binding activity and expression up-regulation in rat cerebral ischaemia is associated with a diminution of neuronal damage in vitro.

Brain plasticity provides a mechanism to compensate for lesions produced as a result of stroke. The present study aims to identify new transcription factors (TFs) following focal cerebral ischaemia in rat as potential therapeutic targets. A transient focal cerebral ischaemia model was used for TF-binding activity and TF-TF interaction profile analysis. A permanent focal cerebral ischaemia model was used for the transcript gene analysis and for the protein study. The identification of TF variants, mRNA analysis, and protein study was performed using conventional polymerase chain reaction (PCR), qPCR, and Western blot and immunofluorescence, respectively. Rat cortical neurons were transfected with small interfering RNA against the TF in order to study its role. The TF-binding analysis revealed a differential binding activity of the octamer family in ischaemic brain in comparison with the control brain samples both in acute and late phases. In this study, we focused on Oct-2 TF. Five of the six putative Oct-2 transcript variants are expressed in both control and ischaemic rat brain, showing a significant increase in the late phase of ischaemia. Oct-2 protein showed neuronal localisation both in control and ischaemic rat brain cortical slices. Functional studies revealed that Oct-2 interacts with TFs involved in important brain processes (neuronal and vascular development) and basic cellular functions and that Oct-2 knockdown promotes neuronal injury. The present study shows that Oct-2 expression and binding activity increase in the late phase of cerebral ischaemia and finds Oct-2 to be involved in reducing ischaemic-mediated neuronal injury.

Systemic autoimmunity in TAM triple knockout mice causes inflammatory brain damage and cell death.

The Tyro3, Axl and Mertk (TAM) triply knockout (TKO) mice exhibit systemic autoimmune diseases, with characteristics of increased proinflammatory cytokine production, autoantibody deposition and autoreactive lymphocyte infiltration into a variety of tissues. Here we show that TKO mice produce high level of serum TNF-α and specific autoantibodies deposited onto brain blood vessels. The brain-blood barrier (BBB) in mutant brains exhibited increased permeability for Evans blue and fluorescent-dextran, suggesting a breakdown of the BBB in the mutant brains. Impaired BBB integrity facilitated autoreactive T cells infiltrating into all regions of the mutant brains. Brain autoimmune disorder caused accumulation of the ubiquitin-reactive aggregates in the mutant hippocampus, and early formation of autofluorescent lipofuscins in the neurons throughout the entire brains. Chronic neuroinflammation caused damage of the hippocampal mossy fibers and neuronal apoptotic death. This study shows that chronic systemic inflammation and autoimmune disorders in the TKO mice cause neuronal damage and death.

Hypervigilance for fear after basolateral amygdala damage in humans.

Recent rodent research has shown that the basolateral amygdala (BLA) inhibits unconditioned, or innate, fear. It is, however, unknown whether the BLA acts in similar ways in humans. In a group of five subjects with a rare genetic syndrome, that is, Urbach-Wiethe disease (UWD), we used a combination of structural and functional neuroimaging, and established focal, bilateral BLA damage, while other amygdala sub-regions are functionally intact. We tested the translational hypothesis that these BLA-damaged UWD-subjects are hypervigilant to facial expressions of fear, which are prototypical innate threat cues in humans. Our data indeed repeatedly confirm fear hypervigilance in these UWD subjects. They show hypervigilant responses to unconsciously presented fearful faces in a modified Stroop task. They attend longer to the eyes of dynamically displayed fearful faces in an eye-tracked emotion recognition task, and in that task recognize facial fear significantly better than control subjects. These findings provide the first direct evidence in humans in support of an inhibitory function of the BLA on the brain's threat vigilance system, which has important implications for the understanding of the amygdala's role in the disorders of fear and anxiety.

Granulin mutation drives brain damage and reorganization from preclinical to symptomatic FTLD.

Granulin (GRN) mutations have been identified as a major cause of frontotemporal lobar degeneration (FTLD) by haploinsufficiency mechanism, although their effects on brain tissue dysfunction and damage still remain to be clarified. In this study, we investigated the pattern of neuroimaging abnormalities in FTLD patients, carriers and noncarriers of GRN Thr272fs mutation, and in presymptomatic carriers. We assessed regional gray matter (GM) atrophy, and resting (RS)-functional magnetic resonance imaging (fMRI). The functional connectivity maps of the salience (SN) and the default mode (DMN) networks were considered. Frontotemporal gray matter atrophy was found in all FTLD patients (more remarkably in those GRN Thr272fs carriers), but not in presymptomatic carriers. Functional connectivity within the SN was reduced in all FTLD patients (again more remarkably in those mutation carriers), while it was enhanced in the DMN. Conversely, presymptomatic carriers showed increased connectivity in the SN, with no changes in the DMN. Our findings suggest that compensatory mechanisms of brain plasticity are present in GRN-related FTLD, but with different patterns at a preclinical and symptomatic disease stage.

Toward genotype phenotype correlations in GFM1 mutations.

Multiple respiratory chain deficiencies represent a common cause of mitochondrial diseases. We report two novel GFM1 mutations in two unrelated patients with encephalopathy and liver failure respectively. The first patient had intrauterine growth retardation, seizures, encephalopathy and developmental delay. Brain MRI showed hypoplasia of the vermis and severe pontine atrophy of the brainstem that were similar to those reported in patients with mitochondrial translation deficiencies. The second patient had liver failure with hypoglycemia. Respiratory chain analysis showed a complex IV deficiency in muscle of both patients. A 10K SNP genotyping detected several regions of homozygosity in the two patients. In vitro translation deficiency prompted us to study genes involved in mitochondrial translation. Therefore, we sequenced the GFM1 gene, encoding the mitochondrial translation factor EFG1, included in a shared homozygous region and identified two different homozygous mutations (R671C and L398P). Modeling studies of EFG1 protein suggested that the R671C mutation disrupts an inter-subunit interface and could locally destabilize the mutant protein. The second mutation (L398P) disrupted the H-bond network in a rich-beta-sheet domain, and may have a dramatic effect on local structure. GFM1 mutations have been seldom reported and are associated with different clinical presentation. By modeling the structure of the protein and the position of the various mutations we suggest that the clinical phenotypes of the patients could be related to the localization of the mutations.

[Schizophrenia and cognition: a neurodevelopmental approach]. / Schizophrénie et cognition: perspective neurodéveloppementale.

Accumulating evidence supports the hypothesis of abnormal neurodevelopment in schizophrenia. According to this hypothesis, schizophrenia is the consequence of prenatal abnormalities resulting from the interaction of genetic and environmental factors. In line with this hypothesis, several studies indicate that pregnancy and birth complications are risk factors for developing schizophrenia. At the clinical level, multiple cognitive deficits can be found in schizophrenic patients before illness onset. The neurodevelopmental hypothesis considers these cognitive deficits as the expression of early abnormalities on the central nervous system development. Consistently, brain imaging data show early structural abnormalities and abnormal progressive brain changes in schizophrenia. Finally, genetic and histological data indicate that genes associated with schizophrenia are involved in brain development.

A novel mutation in the SCO2 gene in a neonate with early-onset cardioencephalomyopathy.

Mutations in the SCO2 gene [SCO cytochrome oxidase deficient homolog 2 (yeast)] causing cytochrome c oxidase deficiency have been reported in at least in 26 patients with fatal infantile cardioencephalomyopathy. Mutation 1541G > A affecting protein stability is associated with the majority of cases, and the other 11 described mutations have more serious deleterious structural consequences for the protein product. Reported here is a novel case caused by compound heterozygosity of SCO2. The child presented at the age of 3 weeks with failure-to-thrive, muscular hypotonia, hypertrophic cardiomyopathy, and lactic acidemia. Leigh syndrome was diagnosed based on magnetic resonance imaging findings. Immunohistochemical and enzymatic investigations on muscle indicated totally absent cytochrome c oxidase activity. Both parents had mild mental retardation. Sequence analysis in the patient and in his parents revealed heterozygous mutation c.418G > A in exon 2 inherited from the father and maternally inherited heterozygous insertion of 19bp at position 17 in the coding region of the SCO2 gene. Respiratory chain enzyme activity measurements indicated normal activity in both parents, although the mother's cytochrome c oxidase activity was lower. This gene may be involved in the etiology of the mother's mental retardation.

Galloway-Mowat syndrome: an early-onset progressive encephalopathy with intractable epilepsy associated to renal impairment. Two novel cases and review of literature.

Galloway-Mowat Syndrome (GMS) is an autosomal recessively inherited condition which manifests with severe encephalopathy, featuring microcephaly, developmental delay, and early-onset intractable epilepsy. Patients typically show also renal involvement from the onset. We report two siblings with GMS presenting with early-onset, intractable epilepsy and neurological deterioration, later followed by renal impairment. In both patients intractable epilepsy started during the first months of life and included a combination of spasms, focal and myoclonic/atonic seizures, along with psychomotor retardation and dysmorphic features. One of the patient died from fulminating renal failure at age 6 years. The other patient developed only isolated proteinuria from the age 3 years. Our cases differ from 'classic' GMS, as manifested the clinical and laboratory features of renal involvement only some years later the onset of epilepsy and neurological symptoms. Therefore, the diagnosis of GMS should be considered in infants with intractable epilepsy, encephalopathy, and multiple neurological deficits, also in absence of renal manifestations. The literature data about the electroclinical features of epilepsy in GMS are also reviewed.