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Objective@#To identify potential variant in a child diagnosed as infantile neuroaxonal dystrophy.@*Methods@#Genomic DNA was extracted from peripheral blood samples from the patient and his parents and subjected to next generation sequencing. Suspected variant was verified by PCR and Sanger sequencing. Pathogenicity of the mutation was predicted by using bioinformatic software including SIFT and PolyPhen-2.@*Results@#The child was found to carry compound heterozygous variations c. 668C>A (p.Pro223Gln) and c. 2266C>T (p.Gln756Ter) of the PLA2G6 gene, which were respectively inherited from his father and mother. c. 2266C>T has changed codon 756 (glutamine) into a stop codon, resulting premature termination of peptide chain synthesis. c. 2266C>T has not been reported previously and was predicted to be harmful.@*Conclusion@#The compound variants of c. 668C>A (p.Pro223Gln) and c. 2266C>T (p.Gln756Ter) of the PLA2G6 gene probably underlies the disease in the child. Above finding has enriched the variant spectrum of the PLA2G6 gene.
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Objective To explore the clinical and the genetic features of infantile neuroaxonal dystrophy (INAD).Methods The clinical and laboratory data,neuroimaging examination and genetic testing results of one child with INAD were retrospectively analyzed.Results A 2 years old boy presented motor and verbal dexterity regression and hypotonia.Laboratory findings revealed decreased total iron-binding capacity in serum with increased glutamic oxaloacetic transaminase (AST) and lactic dehydrogenase (LDH).Myoelectrography showed neurogenic impairments of the arms and legs,and the color doppler ultrasound of the heart,video-EEG and brain MRI results were normal.A homozygous mutation of c.1077G＞A was found in PLA2G6 gene of the infant.The infant's parents were heterozygous mutation carriers at this locus.Conclusions PLA2G6 gene mutations cause INAD.
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We herein report a case of infantile neuroaxonal dystrophy (INAD) with protracted course. The 3 year old patient suffered from ataxia, gait disturbance, oculomotor disturbance, psychomotor regression and bilateral pyramida l tract signs since the age of two. Similar neurological symptoms occurred in his elder brother, beginning at the age of one, who eventually died at the age of four. Magnetic Resonance Imaging (MRI) of the patient showed progressive atrophy of cerebral cortex and cerebellum with diffusely increased T2 signal in bilateral cerebellar hemisphere. The patient's brother revealed similar findings. MRI of the suspected cases may facilitate early diagnosis of INAD, and since it is a well-established autosomal recessive neurodegenerative disaese, early and appropriate genetic counseling of the parents is required.