Hereditary spastic paraplegia: a novel mutation and expansion of the phenotype variability in SPG10: Table 1

Abstract Background: Hereditary spastic paraplegia is a heterogeneous group of clinically and genetically neurodegenerative diseases characterized by progressive gait disorder. Hereditary spastic paraplegia can be inherited in various ways, and all modes of inheritance are associated with multiple genes or loci. At present, more than 76 disease-causing loci have been identified in hereditary spastic paraplegia patients. Here, we report a novel mutation in SPAST gene associated with hereditary spastic paraplegia in a Chinese family, further enriching the hereditary spastic paraplegia spectrum. Methods: Whole genomic DNA was extracted from peripheral blood of the 15 subjects from a Chinese family using DNA Isolation Kit. The Whole Exome Sequencing of the proband was analyzed and the result was identified in the rest individuals. RaptorX prediction tool and Protein Variation Effect Analyzer were used to predict the effects of the mutation on protein tertiary structure and function.Results: Spastic paraplegia has been inherited across at least four generations in this family, during which only four HSP patients were alive. The results obtained by analyzing the Whole Exome Sequencing of the proband exhibited a novel disease-associated in-frame deletion in the SPAST gene, and the this mutation also existed in the rest three HSP patients in this family. This in-frame deletion consists of three nucleotides deletion (c.1710_1712delGAA) within the exon 16, resulting in lysine deficiency at the position 570 of the protein (p.K570del). This novel mutation was also predicted to result in the synthesis of misfolded SPAST protein and have the deleterious effect on the function of SPAST protein.Conclusion: In this case, we reported a novel mutation in the known SPAST gene that segregated with HSP disease, which can be inherited in each generation. Simultaneously, this novel discovery significantly enriches the mutation spectrum, which provides an opportunity for further investigation of genetic pathogenesis of HSP.

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Case report on novel mutation in SPAST gene in Polish family with spastic paraplegia

BMC Neurology ◽

10.1186/s12883-019-1561-6 ◽

2019 ◽

Vol 19 (1) ◽

Author(s):

Aleksandra Klimkowicz-Mrowiec ◽

Anna Dziubek ◽

Malgorzata Sado ◽

Marek Karpiński ◽

Agnieszka Gorzkowska

Keyword(s):

Case Report ◽

Genetic Testing ◽

Family History ◽

Lower Limb ◽

Hereditary Spastic Paraplegia ◽

Novel Mutation ◽

Family Members ◽

Spastic Paraplegia ◽

Limb Spasticity ◽

Lower Limb Spasticity

Abstract Background Hereditary spastic paraplegia is a large group of degenerative, neurological disorders characterized by progressive lower limb spasticity and weakness. The disease was investigated precisely but still clinicians often make incorrect or late diagnosis. Our aim was to investigate the genetic background and clinical phenotype of spastic paraplegia in large Polish family. Case presentation A 37 years old woman presented with 4-year history of walking difficulties. On neurological examination, she had signs of upper motor lesion in lower extremities. She denied sphincter dysfunction and her cognition was normal. Her family history was positive for individuals with gait problems. The initial diagnosis was familial spastic paraplegia. Genetic testing identified a novel mutation in SPAST gene. All available family members were examined and had genetic testing. The same mutation in SPAST gene was identified in other affected family members. All patients caring the mutation presented with different phenotypes. Conclusion This study presents a family with spastic paraplegia due to a novel mutation c.1390G›T(p.Glu464Term) in SPAST gene. Affected individuals showed a range of phenotypes that varied in their severity. This case report demonstrates, the signs of hereditary spastic paraplegia can be often misdiagnosed with other diseases. Therefore genetic testing should always be considered in patients with lower limb spasticity and positive family history in order to help to establish the correct diagnosis.

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