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X-linked adrenoleukodystrophy (X-ALD) is an inherited disease caused by a mutation in the adenosine 5'-triphosphate binding cassette subfamily D member 1 (ABCD1) gene encoding a peroxisomal transmembrane protein, which has various clinical manifestations and a rapid progression from initial symptoms to fatal inflammatory demyelination. Therefore, identification of early clinical symptoms and further early diagnosis as well as treatment can effectively prevent disease development. In this study, we reported the laboratory and radiographic features in a rare case of X-ALD with 3-year skin hyperpigmentation as the only manifestation. And the ABCD1 gene was sequenced for the patient and his parents by a high-throughput sequencing method. The results of laboratory examination showed adrenocortical hypofunction and increased serum concentrations of very long-chain fatty acids. Brain MRI showed no obvious abnormal signal shadow. A hemizygous mutation of c.521A>C was detected in the ABCD1 gene of the patient, and his mother has the same site heterozygous mutation. Therefore, this patient was diagnosed as "X-linked adrenoleukodystrophy". During the follow-up, adrenocortical hypothyroidism did not improve, and brain MRI showed few high-FLAIR signals in the white matter of the right radial corona and left parietal lobe, suggesting possible brain injury. X-ALD patients with only skin manifestations but no neurological abnormalities are easily neglected, but early diagnosis and early intervention are important ways to delay the progression of this disease. Therefore, genetic testing for early X-ALD is recommended in all male children patients with skin pigmentation as the sole clinical presentation and subsequent diagnosis of adrenal hypofunction.
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Adrenoleucodistrofia , Hiperpigmentação , Criança , Humanos , Masculino , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/complicações , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Testes Genéticos , Hiperpigmentação/etiologia , Hiperpigmentação/genética , Imageamento por Ressonância Magnética/efeitos adversos , Imageamento por Ressonância Magnética/métodosRESUMO
X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder caused by mutations in the ABCD1 gene, which encodes an ATP-binding cassette transporter protein, ALDP. The disease is characterized by increased concentrations of very long chain fatty acids (VLCFAs) in plasma, adrenal, testicular, and nerve tissues. For this study, our objective was to conduct clinical, molecular, and genetic studies of a Tunisian patient with X-ALD. The diagnosis was based on clinical indications, biochemical analyses, typical brain-scan patterns, and molecular biology; the molecular analyses were based on PCR, long-range PCR, and sequencing. The molecular analysis by long-range PCR and direct sequencing of the ABCD1 gene showed the presence of a de-novo 2794 bp deletion covering the whole of exon 2. Using bioinformatics tools, we demonstrate that the large deletion is located in a region rich with Alu sequences. Furthermore, we suggest that the AluJb sequence could be the cause of the large deletion of intron 1, exon 2, and intron 2, and the creation of a premature stop codon within exon 3. This report is the first report in which we demonstrate the breakpoints and the size of a large deletion in a Tunisian with X-ALD.
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Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/genética , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Adolescente , Adrenoleucodistrofia/etiologia , Códon de Terminação , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Linhagem , Deleção de SequênciaRESUMO
BACKGROUND: This article presents a case study of two white male siblings of 24 and 31 years of age of self-reported Ukrainian ethnicity diagnosed with adrenomyeloneuropathy (AMN) associated with a novel splice site mutation in the ABCD1 gene. AMN represents a form of X-linked adrenoleukodystrophy (X-ALD) characterized by demyelination of the spinal cord and peripheral nerves. The case also presents the first adult haematopoietic stem cell transplant (HSCT) for adrenomyeloneuropathy in Ukraine. The rarity of this mutation and its cerebral involvement and the treatment make this case noteworthy and underscore the significance of reporting it to contribute to the existing medical knowledge. CASE PRESENTATION: The patients of 24 and 31 years initially exhibited progressive gait disturbance, lower extremity pain, and urinary incontinence, with the older sibling experiencing more advanced symptoms of speech, hearing, and vision disturbances. A comprehensive genetic analysis identified an unreported splice site mutation in exon 3 of the ABCD1 gene, leading to the manifestation of AMN. The inheritance pattern was consistent with X-linked recessive transmission. The article also outlines the clinical features, magnetic resonance imaging (MRI), and nerve conduction study (NCS) findings. Moreover, it discusses the genetic profile of the affected individuals and female carriers within the family. The younger sibling underwent HSCT, which was complicated by mediastinal lymph node and lung tuberculosis, adding to the complexity of managing adult ALD patients. CONCLUSIONS: This report emphasizes the importance of genetic testing in diagnosing and comprehending the underlying mechanisms of rare genetic disorders, such as AMN with cerebral involvement. The identification of a novel splice site mutation expands our understanding of the genetic landscape of this condition. Additionally, the challenges and complications encountered during the hematopoietic stem cell transplant procedure underscore the need for cautious consideration and personalized approaches in adult ALD patients.
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Adrenoleucodistrofia , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Masculino , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/terapia , Adrenoleucodistrofia/diagnóstico , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Etnicidade , Fenótipo , Irmãos , UcrâniaRESUMO
The state of California (CA) added X-linked adrenoleukodystrophy (X-ALD) to newborn screening (NBS) in 2016 via the measurement of C26:0-lysophosphatidylcholine (C26:0-LPC) in a two-tier fashion, followed by sequencing of the ABCD1 gene. This has resulted in the identification of individuals with genetic conditions beyond X-ALD that can also result in elevated C26:0-LPC by NBS. We describe the biochemical, molecular, and clinical characteristics of nine patients from two metabolic centers in California who screened positive by NBS for elevated C26:0-LPC between 2016 and 2022 and were ultimately diagnosed with a genetic condition other than X-ALD. Seven individuals were diagnosed with Zellweger spectrum disorder (ZSD) due to biallelic variants in PEX genes. One male was diagnosed with Klinefelter syndrome and one female was found to have an X chromosome contiguous gene deletion syndrome after the identification of a heterozygous VUS and hemizygous VUS variant in ABCD1, respectively. Patients with ZSD had significantly higher first- and second-tier C26:0-LPC levels compared to the two non-ZSD cases. Identification of children with ZSD and atypical patterns of ABCD1 variants is a secondary benefit of NBS for X-ALD, leading to earlier diagnosis, prompt therapeutic initiation, and more accurate genetic counseling. As screening for X-ALD continues via the measurement of C26:0-LPC, our knowledge of additional genetic conditions associated with elevated C26:0-LPC will continue to advance, allowing for increased recognition of other genetic disorders for which early intervention is warranted.
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Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Adrenoleucodistrofia , Triagem Neonatal , Humanos , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/diagnóstico , Masculino , Feminino , Recém-Nascido , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Síndrome de Zellweger/genética , Síndrome de Zellweger/diagnóstico , California , Testes Genéticos/métodosAssuntos
Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/genética , Ácidos Graxos , Caminhada/fisiologia , Adrenoleucodistrofia/líquido cefalorraquidiano , Adulto , Ácidos Graxos/líquido cefalorraquidiano , Humanos , MasculinoRESUMO
X-linked adrenoleukodystrophy (X-ALD) is a rare neurodegenerative disease characterized by genetic mutation of the ABCD1 gene. This gene encodes for transmembrane adrenoleukodystrophy protein (ALDP). Defective ALDP protein results in the accumulation of a very long chain fatty acid (VLCFA) within certain tissues and plasma. X-ALD can initially present as Addison's disease (primary adrenal insufficiency) as the accumulation of VLCFA most importantly occurs in the adrenal gland. Our 20-year-old male patient, a known case of Addison's disease, presented with vision loss, neurologic symptoms, and psychiatric issues. Neurologic symptoms included poor concentration and memory, while psychiatric problems included primarily depressive disorder and mild psychotic behavior. His Addison's disease was secondary to X-ALD. Still, he was diagnosed late due to a lack of awareness of X-ALD and a lack of resources for genetic testing in Pakistan. Therefore, the purpose of this case report is to spread knowledge and understanding of X-ALD, so that it can be ruled out as the potential cause of adrenal insufficiency in young patients, particularly males diagnosed with Addison's disease. Moreover, if the patient presents with Addison's disease and psychiatric issues, they should be tested to rule out X-ALD.
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OBJECTIVES: X-linked adrenoleukodystrophy (X-ALD), is a peroxisomal inborn error of metabolism caused due to the loss of function variants of ABCD1 gene that leads to accumulation of very long chain fatty acids (VLCFAs) in several tissues including the neurological system. Childhood cerebral X-ALD (CCALD) is the most common and severe form of X-ALD, if left untreated. Allogenic hematopoietic stem cell transplantation (HSCT) is the only available therapy that halts neurological deterioration in CCALD. We present 12 patients with several subtypes of X-ALD that were followed-up in a single center. METHODS: Data of 12 patients diagnosed with X-ALD were documented retrospectively. Demographics, age of onset, initial symptoms, endocrine and neurological findings, VLCFA levels, neuroimaging data, molecular genetic analysis of ABCD1 gene, and disease progress were documented. RESULTS: Mean age of initiation of symptoms was 7.9 years and mean age of diagnosis was 10.45 years. Eight patients had the CCALD subtype, while two had the cerebral form of AMN, one had the adult form of cerebral ALD, and one patient had the Addison only phenotype. The most common initial symptoms involved the neurological system. Loes scores varied between 0 and 12. Seven patients with CCALD underwent HSCT, among them three patients died. The overall mortality rate was 25%. CONCLUSIONS: Patients with X-ALD should be carefully followed up for cerebral findings and progression, since there is no genotype-phenotype correlation, and the clinical course cannot be predicted by family history. HSCT is the only available treatment option for patients with neurological deterioration.
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Adrenoleucodistrofia/patologia , Córtex Cerebral/patologia , Índice de Gravidade de Doença , Adolescente , Adrenoleucodistrofia/terapia , Adulto , Criança , Pré-Escolar , Família , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: Adrenoleukodystrophy (ALD) is a rare sex-linked recessive disorder that disrupts adrenal gland function and the white matter of the nervous system. According to recent epidemiological statistics, up to this moment, the disease is the most recorded peroxisomal disorder. ABCD1 is a gene related to ALD, with more than 850 unique mutations have been reported. Early diagnosis of the disease would help to consult families with ALD to plan for interventions to prevent passing along the pathogenic mutations to their children. MATERIAL AND METHODS: A heterozygous ABCD1 gene mutation related to ALD found in a Vietnamese woman was used to design primers for the polymerase chain reaction (PCR) to amplify the segment spanning the mutation. Then, combining sequencing methods for the PCR products, especially Sanger sequencing and next-generation sequencing (NGS), a protocol was developed to detect mutations on the ABCD1 gene to apply for the DNA samples of in-vitro fertilization (IVF) embryos biopsied at the blastocyst stage to screen for pathogenic alleles. RESULTS: The established protocol for PGD of ALD detected mutant alleles in 5/8 embryos (62.5%), while the remaining 3 embryos (37.5%) did not carry any mutation. One of the 3 embryos was transferred, and a healthy female baby was born after a full-term pregnancy. CONCLUSION: The developed protocol was helpful for the preimplantation genetic diagnosis process to help families with the monogenic disease of ALD but wish to have healthy children.
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X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder that primarily affects the white matter of central nervous system and the adrenal cortex. It is caused by mutations in the adenosine triphosphate-binding cassette, subfamily D, member 1 (ABCD1) gene that results in elevated plasma levels of very long chain fatty acids (VLCFAs). The disease is characterized by an unpredictable variation in phenotypic expressions, including childhood cerebral form (CCALD) and adrenomyeloneuropathy (AMN). Genetic analysis is a reliable method for the diagnosis of X-ALD. We reported a 46-year-old male admitted to Department of Neurology, Chang Gung Memorial Hospital with progressive paraparesis and Addison's disease, which was diagnosed when he was around 20-year-old. Plasma levels of VLCFA showed that his C26:0, C24:0/C22:0 and C26:0/C22:0 ratios were significantly elevated. A novel missense mutation (p.Arg163Cys) caused by the nucleotide change c.487C > T in exon 1 was identified in the ABCD1 gene of the proband and his subclinical family members. In this article, we reviewed the mutations that had been reported at the same position with different phenotypes. Given that the nerve conduction study (NCS) of the proband demonstrated a rare finding of demyelinating polyneuropathy with conduction blocks, we also reviewed the findings of NCS in patients with AMN in literature.
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Adrenoleucodistrofia , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Mutação de Sentido Incorreto , Fenótipo , Adulto JovemRESUMO
Adrenomyeloneuropathy (AMN) is a kind of varied disease caused by ABCD1 gene mutation and characterized by very-long-chain fatty acids (VLCFA) accumulation. It is diagnosed by clinical features, high VLCFAs levels and ABCD1 gene mutation. AMN is rarely reported in Chinese population. In this study, we report the genetic and clinical features of a Chinese pure AMN patient. Meanwhile, we conducted a literature review of AMN cases to summarize the characteristics of AMN. We report a rare Chinese pure AMN case with slowly progressive weakness of the lower extremities, caused by a novel c.1202G > A mutation in ABCD1 gene. The literature review indicates that spastic paraplegia is the mainly clinical manifestation in patients with AMN. VLCFAs and ABCD1 gene test should be performed in patients with spastic paraplegia of the lower limbs to diagnose AMN.
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X-linked adrenoleukodystrophy (X-ALD) is the most frequent type of inherited demyelinating peroxisomal disease caused by mutations in the ATP binding cassette subfamily D member 1 (ABCD1) gene. The rate of early recognition and genetic diagnosis of X-ALD remains low due to its variable clinical manifestations. The present study summarized the clinical features Chinese X-ALD patients and performed a follow-up study to further precisely characterize this disease. A total of 10 patients diagnosed with X-ALD between 1994 and 2016 at Shandong Provincial Hospital Affiliated to Shandong University (Jinan, China) were included in the present study. Through reviewing their medical records and performing telephone follow-ups, the clinical features, biochemical laboratory data, brain images, treatments and long-term outcomes were retrospectively summarized. Mutation analysis of the ABCD1 gene was performed in certain patients. Most of the patients (8/10) had the childhood cerebral form of X-ALD. One patient presented with the olivo-ponto-cerebellar form, the rarest form of X-ALD. In all patients, brain magnetic resonance images revealed abnormalities with typical T2-weighted hyperintensity. Analysis of very long chain fatty acid revealed high plasma levels of hexacosanoic acid in all patients. Increased adrenocorticotropic hormone, decreased cortisol and neurophysiological manifestations were also observed. Three different mutations of the ABCD1 gene were identified in the 3 patients subjected to genotyping. During the follow-ups, most patients took neurotrophic drugs and received hydrocortisone replacement when required. One patient received a hematopoietic stem cell transplantation, but died 1 year following the transplantation. Chronic myelopathy and peripheral neuropathy progressed with time, gradually leading to a vegetative state or paralysis within several years of clinical symptom onset. In conclusion, male patients with adrenocortical insufficiency should be further investigated for X-ALD. Early detection is critical to prevent the progression of X-ALD with mutation analysis of ABCD1 the most accurate method to confirm diagnosis.
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Objective:To analyze the clinical features and genetic background of adrenoleukodystrophy(ALD).Methods:In this study, we reported a rare case of ALD who initially presented with progressive bilateral lower limb weakness. The clinical data of the patient and his family members were collected and the ABCD1 gene was sequenced for the patient and his three daughters by a high-throughput sequencing method.Results:The proband had a later onset of symptoms, a prolonged course of the disease, and initially exhibited bilateral lower limb weakness and nocturnal muscle spasms. The disease progressed to spastic quadriplegia, aphasia, dementia, swallowing difficulties, and urinary and fecal incontinence. Serum very-long-chain fatty acid concentrations were elevated. Subclinical cortisol secretion abnormalities were observed. Cranial imaging indicated symmetrical reduction in density around the lateral ventricles and white matter degeneration. The proband′s ABCD1 gene analysis revealed a novel heterozygous mutation c. 1367G>A, p. R456H. His three daughters carried the same nucleotide heterozygous mutation.Conclusion:This study investigates the clinical characteristics of ALD, providing additional clinical evidence for the diagnosis and treatment of this condition. Additionally, a novel mutation in the ABCD1 gene was identified, contributing to the genetic variation database.
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X-linked adrenoleukodystrophy (X-ALD) is the most common peroxisomal disorder. Adult-onset X-ALD characterized by brainstem symptoms is a rare phenotype of the disease. A male youth of adult-onset X-ALD characterized by brainstem symptoms in Tianjin Huanhu Hospital at April 12, 2021 is reported. The patient mainly presented with progressively gait disturbance, dysarthria and ataxia, which were consistent with the clinical diagnosis of X-ALD in combination with other ancillary tests. Genetic testing suggested the presence of a hemizygous mutation site in the ABCD1 gene. The clinical, imaging and genetic characteristics of X-ALD patients in the literature with brain stem lesion are also summarized, thereby improving the understanding of the rare clinical phenotype of X-ALD.
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X-linked adrenoleukodystrophy (X-ALD) is the most common peroxisomal disorder. It is a heterogeneous disorder caused by mutations in the ATP-binding cassette protein subfamily D1 (ABCD1) gene, encoding the peroxisomal membrane protein ALDP, which is involved in the transmembrane transport of very long-chain fatty acids. For the first time, we report a case of olivopontocerebellar X-ALD on the Chinese mainland. In this study, a novel mutation (c.447T>A; p.S149R) in ABCD1 was detected in a patient diagnosed with X-ALD. The mutant amino acid is well conserved among species. Bioinformatics analysis predicted the substitution to be deleterious and to cause structural changes in the adrenoleukodystrophy protein. Immunofluorescence showed an altered subcellular localization of the S149R mutant protein, which may lead to defects in the degradation of very long chain fatty acids in peroxisomes. We therefore suggest that the novel mutation, which alters ALDP structure, subcellular distribution and function, is responsible for X-ALD.
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OBJECTIVES: X-linked adrenoleukodystrophy is a neurodegenerative disorder caused by mutations in the ABCD1 gene. Adrenomyeloneuropathy and childhood cerebral Adrenoleukodystrophy are the most common phenotypes. This paper focuses on a descriptive study of the first program of diagnosis, treatment, and follow-up of this disease in Morocco. RESULTS: We developed three protocols of X-linked Adrenoleukodystrophy management: general protocol, asymptomatic protocol, and heterozygous protocol. Over a period of 5 years, we recruited eight families with 16 patients. Clinically, the presentation is primary adrenal insufficiency and behavioral changes. All patients had elevated levels of very long fatty acids. This is the first study of X-linked adrenoleukodystrophy in Morocco. It shows the importance of this metabolic disease and broadens perspectives in terms of its diagnosis and its treatment.
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Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/terapia , Adrenoleucodistrofia/epidemiologia , Adulto , Criança , Pré-Escolar , Protocolos Clínicos , Feminino , Humanos , Masculino , Marrocos/epidemiologia , Desenvolvimento de Programas , Doenças RarasRESUMO
Objective:To summarize the clinical manifestations, imaging characteristics, and diagnoses basis of adrenomyeloneuropathy (AMN).Methods:The clinical data of 3 patients with AMN, admitted to our hospital from November 2016 to April 2019, were retrospectively collected. The clinical manifestations, imaging features, and diagnostic process of these patients were analyzed.Results:Three young male patients had onset with gradual aggravation of unilateral or bilateral lower limb insufficiency. MR imaging showed symmetrical abnormal signals in brainstem in 2 patients, and atrophy of thoracic spinal cord in 1 patient. By target region capture sequencing, mutations in the ABCD1 gene were found in all 3 patients; 2 underwent pedigree validation; the remaining one patient and his mother had failed Sanger sequencing validation due to pseudogene interference, and elevated plasma level of very long chain fatty acid (VLCFA) was noted in this patient. Conclusions:AMN usually initiates in the adulthood with spastic paraplegia as onset. Symmetrical lesions in brainstem or atrophy of spinal cord can be manifested on MR imaging; some patients may be accompanied by adrenocortical insufficiency. The definite diagnosis mainly depends on genetic screening and determination of VLCFA level in the blood.
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INTRODUCTION: X-linked adrenoleukodystrophy is a neurodegenerative recessive disorder that affects the brain white matter and associated with adrenal insufficiency. It is characterized by an abnormal function of the peroxisomes, which leads to an accumulation of the Very Long Chain Fatty Acids (VLCFA) in plasma and tissues, especially in the cortex of the adrenal glands and the white matter of the central nervous system. Mutations in the ABCD1 gene affect the function of the encoded protein ALDP, an ATP-binding cassette transporter located in the peroxisomal membrane protein. PATIENTS AND METHODS: The present study reports the clinical, biochemical and molecular investigation in a Tunisian family with two affected males with childhood cerebral adrenoleukodystrophy. RESULTS: The ABCD1 gene sequencing indicated a novel hemizygous missense mutation c.947A>C (p.Gln316Pro) in the exon 2 of the ABCD1 gene in the patients, their mother and their sisters. This missense variation was predicted to be possibly damaging by the PolyPhen and SIFT prediction software. Although presence of the same mutation c.947A>C in both siblings, they present different clinical signs. CONCLUSIONS: Based on the disease's progress, the clinical signs and biochemical aspects between the two siblings, we demonstrate that there is no correlation genotype-phenotype.
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Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/genética , Mutação de Sentido Incorreto , Fenótipo , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/metabolismo , Sequência de Bases , Encéfalo/metabolismo , Criança , Éxons/genética , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Irmãos , TunísiaRESUMO
X-linked adrenoleukodystrophy (X-ALD) affects the nervous system white matter and adrenal cortex secondary to mutations in the ABCD1 gene that encodes a peroxisomal membrane protein: the adrenoleukodystrophy protein. The disease is characterized by high concentrations of very long-chain fatty acids in plasma, adrenal, testicular and nervous tissues. Various types of mutations have been identified in the ABCD1 gene: point mutations, insertions, and deletions. To date, more than 40 point mutations have been reported at the splice junctions of the ABCD1 gene; only few functional studies have been performed to explore these types of mutations. In this study, we have identified de novo splice site mutation c.1780+2T>G in ABCD1 gene in an X-ALD Tunisian patient. Sequencing analysis of cDNA showed a minor transcript lacking exon 7 and a major transcript with a partial intron 7 retention due to activation of a new intronic cryptic splice site. Both outcomes lead to frameshifts with premature stop codon generation in exon 8 and intron 7 respectively. To the best of our knowledge, the current study demonstrates that a single splicing mutation affects the ABCD1 transcripts and the ALDP protein function.
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Transportadores de Cassetes de Ligação de ATP/genética , Adrenoleucodistrofia/genética , Éxons , Íntrons , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP , Adolescente , Adrenoleucodistrofia/patologia , Encéfalo/patologia , Humanos , Masculino , Mutação , TunísiaRESUMO
X-linked adrenoleukodystrophy (X-ALD) is a rare peroxisomal disorder, that is rapidly progressive, neurodegenerative, and recessive, and characteristically primary affects the central nervous system white matter and the adrenal cortex. X-ALD is diagnosed basaed on clinical, radiological, and serological parameters, including elevated plasma levels of very long chain fatty acids (VLCFA), such as C24:0 and C26:0, and high C24:0/C22:0 and C26:0/C22:0 ratios. These tests are complemented with genetic analyses. A 7.5-year-old boy was admitted to Department of Pediatrics, Chungnam National University Hospital with progressive weakness of the bilateral lower extremities. Brain magnetic resonance imaging confirmed clinically suspected ALD. A low dose adrenocorticotropic hormone stimulation test revealed parital adrenal insufficiency. His fasting plasma levels of VLCFA showed that his C24:0/C22:0 and C26:0/C22:0 ratios were significantly elevated to 1.609 (normal, 0-1.390) and 0.075 (normal, 0-0.023), respectively. Genomic DNA was extracted from peripheral whole blood samples collected from the patient and his family. All exons of ABCD1 gene were amplified by polymerase chain reaction (PCR) using specific primers. Amplified PCR products were sequenced using the same primer pairs according to the manufacturer's instructions. We identified a missense mutation (p.Arg163Leu) in the ABCD1 gene of the proband caused by the nucleotide change 488G>T in exon 1. His asymptomatic mother carried the same mutation. We have reported an unpublished mutation in the ABCD1 gene in a patient with X-ALD, who showed increased ratio of C24:0/C22:0 and C26:0/C22:0, despite a normal VLCFA concentrations.
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Objective To identify the clinical manifestations, imaging findings, and genetic mutation characteristics in an uncommon case of adrenoleukodystrophy ( ALD) with adrenocortical dysfunction ( Addison's disease) as the first manifestation. Methods The clinical data of the proband and his family members were comprehensively collected, and ABCDl gene sequencing was meticulously performed for the proband and his mother using high-throughput sequencing method. Results The patient presented with systematical skin pigmentation accompanied by fatigue in early stage, arose stroke-like episodes manifested as a sudden loss of consciousness and incontinence induced by high fever, and followed by progressive unclear speech, unstable walking and worsening vision. Serum very long-chain fatty acid (VLCFA) concentration increased over normal range. The brain MRI showed an abnormal signal of the symmetric distribution of the bilateral corpus callosum. A new c. 874 876del GAG hemizygous variation in the patient's ABCD1 gene was detected, while his mother had a nucleotide heterozygous variation to this site . Conclusion The diagnosis of ALD requires a combination of clinical manifestations, imaging examination, and serum VLCFA levels, while the detection of ABCD1 gene mutations is considered to be the most reliable approach.