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Congenital disorders of glycosylation type 1 (CDG-I) comprise a group of 27 genetic defects with heterogeneous multisystem phenotype, mostly presenting with nonspecific neurological symptoms. The biochemical hallmark of CDG-I is a partial absence of complete N-glycans on transferrin. However, recent findings of a diagnostic N-tetrasaccharide for ALG1-CDG and increased high-mannose N-glycans for a few other CDG suggested the potential of glycan structural analysis for CDG-I gene discovery. We analyzed the relative abundance of total plasma N-glycans by high resolution quadrupole time-of-flight mass spectrometry in a large cohort of 111 CDG-I patients with known (n = 75) or unsolved (n = 36) genetic cause. We designed single-molecule molecular inversion probes (smMIPs) for sequencing of CDG-I candidate genes on the basis of specific N-glycan signatures. Glycomics profiling in patients with known defects revealed novel features such as the N-tetrasaccharide in ALG2-CDG patients and a novel fucosylated N-pentasaccharide as specific glycomarker for ALG1-CDG. Moreover, group-specific high-mannose N-glycan signatures were found in ALG3-, ALG9-, ALG11-, ALG12-, RFT1-, SRD5A3-, DOLK-, DPM1-, DPM3-, MPDU1-, ALG13-CDG, and hereditary fructose intolerance. Further differential analysis revealed high-mannose profiles, characteristic for ALG12- and ALG9-CDG. Prediction of candidate genes by glycomics profiling in 36 patients with thus far unsolved CDG-I and subsequent smMIPs sequencing led to a yield of solved cases of 78% (28/36). Combined plasma glycomics profiling and targeted smMIPs sequencing of candidate genes is a powerful approach to identify causative mutations in CDG-I patient cohorts., (© 2022 The Authors. Journal of Inherited Metabolic Disease published by John Wiley & Sons Ltd on behalf of SSIEM.)

Long non-coding RNAs (lncRNAs) can be important components in gene-regulatory networks 1 , but the exact nature and extent of their involvement in human Mendelian disease is largely unknown. Here we show that genetic ablation of a lncRNA locus on human chromosome 2 causes a severe congenital limb malformation. We identified homozygous 27-63-kilobase deletions located 300 kilobases upstream of the engrailed-1 gene (EN1) in patients with a complex limb malformation featuring mesomelic shortening, syndactyly and ventral nails (dorsal dimelia). Re-engineering of the human deletions in mice resulted in a complete loss of En1 expression in the limb and a double dorsal-limb phenotype that recapitulates the human disease phenotype. Genome-wide transcriptome analysis in the developing mouse limb revealed a four-exon-long non-coding transcript within the deleted region, which we named Maenli. Functional dissection of the Maenli locus showed that its transcriptional activity is required for limb-specific En1 activation in cis, thereby fine-tuning the gene-regulatory networks controlling dorso-ventral polarity in the developing limb bud. Its loss results in the En1-related dorsal ventral limb phenotype, a subset of the full En1-associated phenotype. Our findings demonstrate that mutations involving lncRNA loci can result in human Mendelian disease.

Acute necrotizing encephalopathy (ANE) is clinically characterized by fever, acute alteration of consciousness, seizures, and rapid progression to coma within days of onset of a viral illness occurring in healthy children without evidence of central nervous system infection. Brain magnetic resonance imaging (MRI) shows multiple symmetrical lesions affecting primarily the thalami but also brain stem, putamina, periventricular white matter, and cerebellum. Most cases of ANE are sporadic and nonrecurrent. However, a missense variant in RANBP2 has been identified in some families with recurrent ANE (OMIM # 608033), also named autosomal dominant ANE (ADANE). Clinical manifestation, clinical course, and brain MRI imaging findings of six affected members of two distinct families with ADANE were described. Sequencing revealed heterozygous c.1754C > T variant in RANBP2 (p.Thr585Met) in affected and asymptomatic family members. Only few ADANE families have been reported and it is the first description in South America. Differential diagnosis of Leigh disease and acute disseminated encephalomyelitis is discussed. Our report reinforces incomplete penetrance of ADANE and intrafamilial phenotypic variability of outcome., Competing Interests: Conflict of Interest None declared., (Thieme. All rights reserved.)

Variants in MBTPS1 (membrane-bound transcription factor peptidase, site 1) encoding the protein convertase site-1 protease (S1P) were recently reported in a single individual with skeletal dysplasia and elevated plasma lysosomal enzymes. Here, we report the second individual with this newly described autosomal recessive spondyloepiphyseal dysplasia (OMIM #618392), presenting severe growth retardation, cataract and dysmorphic features, mainly retromicrognathia. Epilepsy and craniosynostosis were novel findings in our proband. She was found to be homozygous for a novel nonsense variant p.Trp983Ter in MBTPS1. In addition, she had normal levels of lysosomal enzyme activity in leukocytes but elevated levels in plasma. Our description confirms the existence of this new skeletal dysplasia and expands the phenotype and genotype of the disease., (© 2020 Wiley Periodicals, Inc.)

ATP7A encodes a copper-transporting P-type ATPase and is one of 23 genes in which mutations produce distal hereditary motor neuropathy (dHMN), a group of diseases characterized by length-dependent axonal degeneration of motor neurons. We have generated induced pluripotent stem cell (iPSC)-derived motor neurons from a patient with the p.T994I ATP7A gene mutation as an in vitro model for X-linked dHMN (dHMNX). Patient motor neurons show a marked reduction of ATP7A protein levels in the soma when compared to control motor neurons and failed to upregulate expression of ATP7A under copper-loading conditions. These results recapitulate previous findings obtained in dHMNX patient fibroblasts and in primary cells from a rodent model of dHMNX, indicating that patient iPSC-derived motor neurons will be an important resource for studying the role of copper in the pathogenic processes that lead to axonal degeneration in dHMNX., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

We report a patient who was followed for a long time under an ectrodactyly ectodermal dysplasia-clefting (EEC) syndrome and was subsequently diagnosed with a 19q13.11 microdeletion. After a review of the related literature, we suggest testing patients with EEC for 19q13.11 microdeletion and include WTIP and UBA2 to a minimal overlapping region.

Background: Multiple osteochondromas is a dysplasia characterized by growth of two or more osteochondromas. It is genetically heterogeneous, caused by pathogenic variants in EXT1 or EXT2 genes in 70%-90% of patients. The EXT1 is more often mutated than EXT2 gene, with a variable prevalence between populations. There are no data about EXT1 and EXT2 pathogenic variants in patients with multiple osteochondromas in Brazilian population. The aim of this survey is to characterize these to determine the genotype profile of this population., Methods: DNA sequencing (Sanger Method) and MLPA analysis were performed to identify point mutations and deletions/duplications in the sample of 153 patients in 114 families., Results: Germline variants were identified in 83% of families in which EXT2 variants were detected in 46% and EXT1 in 37% of cases. No variants were detected in 17% of them. We identified 50 different variants, 33 (13 frameshift, 11 nonsense, 5 missense, 2 splice site mutation, and 2 large deletions) in EXT1 and 17 (6 frameshift, 6 splice site mutation, 3 nonsense, 1 missense, and 1 large deletion) in EXT2. Of all 50 variants, 31 (62%) were novel, including 20 out of 33 (60,6%) EXT1 and 11 out of 17 (64.7%) EXT2 alleles. The vast majority of variants (88%) were "loss-of-function" and two novel hotspots in EXT2 gene were observed in our study., Conclusion: The prevalence of variants detected in the EXT2 gene differs from other researches from Latin America, European, and Asian population. This uncommon prevalence could be related with the newly characterized variant hotspot sites detected in EXT2 gene (p.Ala409Profs*26 and p.Ser290*). A high number of novel variants were also identified indicating that Brazilian population has a unique genetic profile. Characterizing this population and establishing its genotype is essential to understand the molecular pathogenesis of this disease in Brazil., (© 2018 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.)

FOXG1 syndrome is caused by FOXG1 intragenic point mutations, or by long-range position effects (LRPE) of intergenic structural variants. However, the size of the FOXG1 regulatory landscape is uncertain, because the associated topologically associating domain (TAD) in fibroblasts is split into two domains in embryonic stem cells (hESC). Indeed, it has been suggested that the pathogenetic mechanism of deletions that remove the stem-cell-specific TAD boundary may be enhancer adoption due to ectopic activity of enhancer(s) located in the distal hESC-TAD. Herein we map three de novo translocation breakpoints to the proximal regulatory domain of FOXG1. The classical FOXG1 syndrome in these and in other translocation patients, and in a patient with an intergenic deletion that removes the hESC-specific TAD boundary, do not support the hypothesised enhancer adoption as a main contributor to the FOXG1 syndrome. Also, virtual 4 C and HiC-interaction data suggest that the hESC-specific TAD boundary may not be critical for FOXG1 regulation in a majority of human cells and tissues, including brain tissues and a neuronal progenitor cell line. Our data support the importance of a critical regulatory region (SRO) proximal to the hESC-specific TAD boundary. We further narrow this critical region by a deletion distal to the hESC-specific boundary, associated with a milder clinical phenotype. The distance from FOXG1 to the SRO ( > 500 kb) highlight a limitation of ENCODE DNase hypersensitivity data for functional prediction of LRPE. Moreover, the SRO has little overlap with a cluster of frequently associating regions (FIREs) located in the proximal hESC-TAD.

Horstick et al. (2013) previously reported a homozygous p.Trp284Ser variant in STAC3 as the cause of Native American myopathy (NAM) in 5 Lumbee Native American families with congenital hypotonia and weakness, cleft palate, short stature, ptosis, kyphoscoliosis, talipes deformities, and susceptibility to malignant hyperthermia (MH). Here we present two non-Native American families, who were found to have STAC3 pathogenic variants. The first proband and her affected older sister are from a consanguineous Qatari family with a suspected clinical diagnosis of Carey-Fineman-Ziter syndrome (CFZS) based on features of hypotonia, myopathic facies with generalized weakness, ptosis, normal extraocular movements, cleft palate, growth delay, and kyphoscoliosis. We identified the homozygous c.851G>C;p.Trp284Ser variant in STAC3 in both sisters. The second proband and his affected sister are from a non-consanguineous, Puerto Rican family who was evaluated for a possible diagnosis of Moebius syndrome (MBS). His features included facial and generalized weakness, minimal limitation of horizontal gaze, cleft palate, and hypotonia, and he has a history of MH. The siblings were identified to be compound heterozygous for STAC3 variants c.851G>C;p.Trp284Ser and c.763_766delCTCT;p.Leu255IlefsX58. Given the phenotypic overlap of individuals with CFZS, MBS, and NAM, we screened STAC3 in 12 individuals diagnosed with CFZS and in 50 individuals diagnosed with MBS or a congenital facial weakness disorder. We did not identify any rare coding variants in STAC3. NAM should be considered in patients presenting with facial and generalized weakness, normal or mildly abnormal extraocular movement, hypotonia, cleft palate, and scoliosis, particularly if there is a history of MH., (© 2017 Wiley Periodicals, Inc.)

ATP7A is a P-type ATPase essential for cellular copper (Cu) transport and homeostasis. Loss-of-function ATP7A mutations causing systemic Cu deficiency are associated with severe Menkes disease or its milder allelic variant, occipital horn syndrome. We previously identified two rare ATP7A missense mutations (P1386S and T994I) leading to a non-fatal form of motor neuron disorder, X-linked distal hereditary motor neuropathy (dHMNX), without overt signs of systemic Cu deficiency. Recent investigations using a tissue specific Atp7a knock out model have demonstrated that Cu plays an essential role in motor neuron maintenance and function, however the underlying pathogenic mechanisms of ATP7A mutations causing axonal degeneration remain unknown. We have generated an Atp7a conditional knock in mouse model of dHMNX expressing Atp7a(T985I), the orthologue of the human ATP7A(T994I) identified in dHMNX patients. Although a degenerative motor phenotype is not observed, the knock in Atp7a(T985I/Y) mice show altered Cu levels within the peripheral and central nervous systems, an increased diameter of the muscle fibres and altered myogenin and myostatin gene expression. Atp7a(T985I/Y) mice have reduced Atp7a protein levels and recapitulate the defective trafficking and altered post-translational regulatory mechanisms observed in the human ATP7A(T994I) patient fibroblasts. Our model provides a unique opportunity to characterise the molecular phenotype of dHMNX and the time course of cellular events leading to the process of axonal degeneration in this disease.

Background and Purpose: Hyperargininemia (HA) is a rare autosomal recessive metabolic disorder and the neuroimaging features of this disease have seldom been reported. Hyperammonemic encephalopathy is uncommon in HA, and the clinical presentation of HA is distinct from other urea cycle disorders. This paper describes the brain MRI findings and a magnetic resonance spectroscopy (MRS) study of a series of Brazilian HA patients., Methods: Brain MR images were obtained in eight male and two female patients with the classic HA phenotype. Six patients were evaluated twice. Single-voxel (1)H-MRS was also performed in six of the patients., Results: Only 1 patient, with less severe neurological symptoms, had normal MRI images. A variable degree of cerebral atrophy was noted in the other patients, and 3 patients also presented mild symptoms of cerebellar atrophy. MRS indicated no metabolic abnormalities in any patient., Conclusions: We present the MRI and MRS findings of a large series of HA patients. Variable degrees of brain atrophy and mild cerebellar atrophy were observed, and these findings were not specific. No metabolic abnormality was observed using MRS in this series of patients., (Copyright © 2012 by the American Society of Neuroimaging.)

Hyperargininemia (HA) is an autosomal recessive disease that typically has a clinical presentation that is distinct from other urea cycle disorders. It is caused by the deficient activity of the enzyme arginase I, encoded by the gene ARG1. We screened for ARG1 mutations and measured erythrocyte enzyme activity in a series of 16 Brazilian HA patients. Novel mutations, in addition to previously described missense mutations, were analysed for their effect on the structure, stability and/or function of arginase I (ARG1) using bioinformatics tools. Three previously reported mutations were found (p.R21X; p.I11T and p.W122X), and five novel mutations were identified (p.G27D; p.G74V; p.T134I; p.R308Q; p.I174fs179). The p.T134I mutation was the most frequent in the Brazilian population. Patients carrying the p.R308Q mutation had higher residual ARG1 decreased activity, but presented no distinguishable phenotype compared to the other patients. Bioinformatics analyses revealed that missense mutations (1) affect the ARG1 active site, (2) interfere with the stability of the ARG1 folded conformation or (3) alter the quaternary structure of the ARG1. Our study reinforced the role of Arg308 residue for assembly of the ARG1 homotrimer. The panel of heterogeneous ARG1 mutations that cause HA was expanded, nevertheless a clear genotype-phenotype correlation was not observed in our series., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Spondylo-megaepiphyseal-metaphyseal dysplasia (SMMD; OMIM 613330) is a dysostosis/dysplasia caused by recessive mutations in the homeobox-containing gene, NKX3-2 (formerly known as BAPX1). Because of the rarity of the condition, its diagnostic features and natural course are not well known. We describe clinical and radiographic findings in six patients (five of which with homozygous mutations in the NKX3-2 gene) and highlight the unusual and severe changes in the cervical spine and the neurologic complications. In individuals with SMMD, the trunk and the neck are short, while the limbs, fingers and toes are disproportionately long. Radiographs show a severe ossification delay of the vertebral bodies with sagittal and coronal clefts, missing ossification of the pubic bones, large round "balloon-like" epiphyses of the long bones, and presence of multiple pseudoepiphyses at all metacarpals and phalanges. Reduced or absent ossification of the cervical vertebrae leads to cervical instability with anterior or posterior kinking of the cervical spine (swan neck-like deformity, kyknodysostosis). As a result of the cervical spine instability or deformation, five of six patients in our series suffered cervical cord injury that manifested clinically as limb spasticity. Although the number of individuals observed is small, the high incidence of cervical spine deformation in SMMD is unique among skeletal dysplasias. Early diagnosis of SMMD by recognition of the radiographic pattern might prevent of the neurologic complications via prophylactic cervical spine stabilization., (Copyright © 2012 Wiley Periodicals, Inc.)

Hyperargininemia is an autosomal recessive metabolic disorder caused by a deficiency of enzyme arginase I. It is a rare pan-ethnic disease with a clinical presentation distinct from that of other urea cycle disorders, and hyperammonemic encephalopathy is not usually observed. Hyperargininemia is one of the few treatable causes of pediatric spastic paraparesis, and can be confused with cerebral palsy. We retrospectively evaluated the clinical onset, neurologic manifestations, progression of abnormalities, electroencephalographic abnormalities, and laboratory findings of 16 Brazilian patients with hyperargininemia. Relevant data about the clinical spectrum and natural history of hyperargininemia are detailed. Progressive spastic diplegia constituted the key clinical abnormality in this group, but variability in clinical presentation and progression were evident in our series. Seizures in hyperargininemia may be more common than reported in previous studies. Features distinguishing hyperargininemia from cerebral palsy and hereditary spastic paraplegia are emphasized in this large series of patients., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Langer-Giedion syndrome (LGS) (OMIM 150230) is defined as a contiguous gene syndrome caused by loss of functional copies of the TRPS1 and EXT1 genes usually secondary to 8q microdeletion. Tibial hemimelia (TH) is the least common lower limb deficiency characterized by hypoplasia of the tibia with relatively intact fibula. We describe the third report of LGS with bilateral TH and an 8q23.1-q24.12 interstitial deletion. It is not possible to exclude that this association is fortuitous, but our report reinforces the suggestion of a putative gene involved in limb development in this chromosomal region interval., (Copyright © 2011 Wiley Periodicals, Inc.)

Primrose syndrome is a unique condition of intellectual disability, dysmorphic facial features, and specific minor abnormalities including large calcified ear auricles. Only six patients have been previously reported. We describe a Brazilian boy with the striking similar facies and the main clinical findings that reinforced the singular phenotype of this rare disorder. The key features of all patients already published were compared. Our young patient has abnormalities that were not observed in preceding reports: nail dysplasia and hyperuricemia., (Copyright © 2011 Wiley-Liss, Inc.)

Objective: The aim of this study was the evaluation by using computerized tomography (CT) of craniofacial abnormalities in fibrodysplasia ossificans progressiva (FOP) patients regarding jaw restriction and retrognathia., Study Design: Seven FOP patients were evaluated retrospectively in this observational study. Inclusion criteria were detection of ACVR1 gene mutation and complete craniofacial CT examination. The age of jaw restriction and presence of retrognathia were clinically determined. The features analyzed were skull base structures and heterotopic ossification (HO)., Results: Of this group (age range 4-23 years), the 3 oldest patients presented with jaw restriction and retrognathia as well as displayed elongation of the lateral pterygoid plate with HO of the pterygoid muscles that reached the medial surface of the right mandibular ramus. They had significant history of trauma or surgery. The other 4 patients did not have retrognathia or HO involving the facial or masticatory muscles, and the mouth opening was normal., Conclusions: CT evaluation can reveal HO of the pterygoid muscles that probably may cause jaw restriction and retrognathia in older FOP patients., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Aim: Apolipoprotein E (APOE, protein; [ApoE, gene]) is a lipid transport protein abundantly present in brain cells. We investigated whether the APOE genotype is associated with cerebral palsy (CP) and whether patients with CP with comorbid conditions and more severe neurological deficits are likely to have a particular genotype., Method: In a cross-sectional study, 243 individuals with spastic CP (135 males, 108 females; mean age at data collection 11 year ([SD 6y 7mo], 34% with hemiplegia, 37% with diplegia, 29% with triplegia/tetraplegia; 44% with mild motor involvement), 31% with moderate motor involvement, 25% with severe motor involvement, were compared with healthy individuals matched by age, race, and sex to analyse the association between APOE genotype and the incidence of CP. Associations between the APOE genotype and the incidence of comorbidities and neurological deficits were studied in the group with CP., Results: The APOE epsilon2epsilon3 genotype was significantly more prevalent in the group with CP (11%) than the comparison group (5%) (odds ratio [OR] 2.8; 95% confidence interval [CI] 1.01-7.66). The presence of the epsilon2 allele raised the probability of having CP (OR 3.2; 95% CI 1.27-8.27). The presence of ApoE epsilon4 was not significantly different among groups. No relation was found between APOE genotype and severity of neurological deficit or distribution of motor involvement. Four patients with CP presented the epsilon4epsilon4 genotype, and all exhibited epilepsy and microcephaly. Eleven of 12 individuals with CP and macrocephaly carried the epsilon3epsilon3 genotype., Interpretation: A higher prevalence of the APOE epsilon2 genotype was found among those with CP. The association of microcephaly and epilepsy with the epsilon4epsilon4 genotype and the association of macrocephaly with epsilon3 demand further investigation.

Distal hereditary motor neuropathies comprise a clinically and genetically heterogeneous group of disorders. We recently mapped an X-linked form of this condition to chromosome Xq13.1-q21 in two large unrelated families. The region of genetic linkage included ATP7A, which encodes a copper-transporting P-type ATPase mutated in patients with Menkes disease, a severe infantile-onset neurodegenerative condition. We identified two unique ATP7A missense mutations (p.P1386S and p.T994I) in males with distal motor neuropathy in two families. These molecular alterations impact highly conserved amino acids in the carboxyl half of ATP7A and do not directly involve the copper transporter's known critical functional domains. Studies of p.P1386S revealed normal ATP7A mRNA and protein levels, a defect in ATP7A trafficking, and partial rescue of a S. cerevisiae copper transport knockout. Although ATP7A mutations are typically associated with severe Menkes disease or its milder allelic variant, occipital horn syndrome, we demonstrate here that certain missense mutations at this locus can cause a syndrome restricted to progressive distal motor neuropathy without overt signs of systemic copper deficiency. This previously unrecognized genotype-phenotype correlation suggests an important role of the ATP7A copper transporter in motor-neuron maintenance and function., (Copyright 2010 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Fibrodysplasia ossificans progressiva (FOP) is a severe genetic disorder reported worldwide. A specific heterozygous mutation (c.617G> A; p.R206H) in the activin A type I receptor gene (ACVR1) is regarded as the genetic cause of FOP in all classically affected individuals worldwide. However, a few patients with FOP variants harbor distinct mutations in ACVR1. We screened a group of FOP Brazilian population for mutations in ACVR1. Of 16 patients with a classic FOP phenotype (10 males and 6 females, age range of 3-42 years), all had the classic mutation (p.R206H). One 21-year-old woman with a variant FOP phenotype had the previously reported c.983G> A mutation (p.G328E). Our study contributes to the understanding of the predominant FOP phenotype and genotype and suggests that variant FOP phenotypes are associated with specific mutations in ACVR1 gene.

Magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), and MR spectroscopy (MRS) data were obtained in a patient with giant axonal neuropathy (GAN) and compared to a control group. Fractional anisotropy (FA) and apparent coefficient diffusion (ADC) data were obtained from specific white matter tracts including the corticospinal tracts (CST), corpus callosum (CC), optic radiations (OR), and middle cerebellar peduncle (MCP). Analysis of the MRS was performed. DTI parameters and MRS results were correlated with the neuropathological findings described for GAN. No significant difference between the FA of the CC of the patient and the control group was found. However, there was a significant difference between the FA of the CST, OR, and MCP of the patient and the control group. The ADC values for all tracts of the patient were significantly increased. N-acetylaspartate to creatine (NAA/Cr) and N-acetylaspartate to choline (NAA-Cho) (choline) metabolite ratios were slightly decreased and choline to creatine (Cho/Cr) and myo-inositol to creatine (Ins/Cr) metabolite ratios were increased in the parietal gray and white matter of the patient as compared to the control group. Cerebellar involvement was less evident. The DTI and MRS findings suggest myelin and axonal damage., ((c) 2008 Wiley-Liss, Inc.)

Spinocerebellar ataxia type 3, or Machado-Joseph disease, is an autosomal dominant neurodegenerative disease characterized by a wide spectrum of clinical findings that include progressive cerebellar ataxia. All affected individuals have an expanded CAG repeat mutation in one allele of the ATXN3 gene. An inverse relationship exists between the age of onset and the number of repeats in the abnormal expanded allele. The case described is that of a child with Machado-Joseph disease, daughter of a consanguineous affected couple. She inherited the expanded allele in homozygosity with CAG repeat size similar to that of her parents, and had a distinct early onset (4 years of age) and severe clinical phenotype. This case supports the conclusion that homozygosity aggravates the clinical phenotype. Loss of function of the normal expressed ataxin-3, or possibly aggregation of ataxin-3, may be implicated in disease mechanism.

We report on clinical evaluations of Brazilian patients with misoprostol-induced arthrogryposis. All 15 patients had growth retardation, underdeveloped bones, short feet with equinovarus, rigidity of several joints with skin dimples and webs, decreased movement of legs stemming from neurologic impairment, bilateral symmetrical hypoplasia or atrophy of limb muscles, and absent tendon reflexes. Of the 15 patients, five had upper limb deformities in addition to lower limb involvement, and one had spinal cord disruption leading secondarily to segmental sensory loss and neurogenic bladder and bowel. Electroneuromyography of five patients indicated that the abnormalities were of neurogenic origin and suggestive of anterior horn cell defects. All of their mothers took 400-4,800 mcg of misoprostol orally or vaginally at 8 to 12 weeks of pregnancy. Our observations support a previously stated caution with regard to the embryotoxicity of misoprostol.