Dataset Information

Clinical and genetic analysis of 7 Chinese patients with ?-ureidopropionase deficiency.

ABSTRACT: ?-Ureidopropionase (?UP) deficiency is an autosomal recessive disease caused by abnormal changes in the pyrimidine-degradation pathway. This study aimed to investigate the mutation of ?-ureidopropionase gene (UPB1) gene and clinical features of 7 Chinese patients with ?UP deficiency.We reported 7 Chinese patients with ?UP deficiency who were admitted at Tianjin Children's Hospital. Urine metabolomics was detected by gas chromatography-mass spectrometry (GC-MS). Then genetic testing of UPB1 was conducted by polymerase chain reaction (PCR) method.The patients presented with developmental delay, seizures, autism, abnormal magnetic resonance imaging, and significantly elevated levels of N-carbamyl-?-alanine and N-carbamyl-?-aminoisobutyric acid in urine. Subsequent analysis of UPB1 mutation revealed 2 novel missense mutations (c.851G>T and c.853G>A), 3 previously reported mutations including 2 missense mutations (c.977G>A and c.91G>A) and 1 splice site mutation (c.917-1 G>A).The results suggested that the UPB1 mutation may contribute to ?UP deficiency. The c.977G>A is the most common mutation in Chinese population.

SUBMITTER: Fang Y

PROVIDER: S-EPMC6344145 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Clinical and genetic analysis of 7 Chinese patients with β-ureidopropionase deficiency.

Fang Yulian Y Cai Chunquan C Wang Chao C Sun Bei B Zhang Xinjie X Fan Wenxuan W Hu Wenchao W Meng Yingtao Y Lin Shuxiang S Zhang Chunhua C Zhang Yuqin Y Shu Jianbo J

Medicine 20190101 1

β-Ureidopropionase (βUP) deficiency is an autosomal recessive disease caused by abnormal changes in the pyrimidine-degradation pathway. This study aimed to investigate the mutation of β-ureidopropionase gene (UPB1) gene and clinical features of 7 Chinese patients with βUP deficiency.We reported 7 Chinese patients with βUP deficiency who were admitted at Tianjin Children's Hospital. Urine metabolomics was detected by gas chromatography-mass spectrometry (GC-MS). Then genetic testing of UPB1 was c ...[more]

PMID: 30608453

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Project description:BackgroundPanel-based targeted exome sequencing was applied to identify the pathogenic variants and genetic characteristics of retinitis pigmentosa (RP) in two Chinese families, and to gain a deeper understanding of the relationship between clinical manifestations and genotypes.MethodsA total of 17 subjects, comprising two probands (total patients: four subjects) and their family member, were recruited in this study. All subjects underwent comprehensive ophthalmic examinations and clinical evaluations, and the complete history and medical records were collected according to the standard procedures. All participants were screened using the multigene panel test (Target_Eye_792_V2 chip), and Sanger sequencing was used to confirm the candidate variants.ResultsAmong these two families, a total of three novel mutations in the EYS gene were identified in patients, including a homozygous frameshift mutation c.9252_9253insT detected in two patients in one family, and the compound heterozygous splicesite mutation c.5644+2T>C and frameshift mutation c.1920_1923delTGAG detected in two patients in the another family. All patients in both families had early onset of night blindness and poor visual acuity, and with typical posterior capsule opacification. The mutation co-segregated within all recruited individuals. In addition, one patient with compound heterozygous mutations was found to have typical blue-blindness symptoms and detected a previously reported disease-causing mutation c.235G>A in OPN1SW gene, which caused blue blindness manifestations and was first discovered in patient combined with RP causative genes.ConclusionsPanel-based targeted exome sequencing was used to identify three novel variants of RP causative gene, and we also detected a known pathogenic variants of blue-blindness causative genes in two patients. Our finding will provide a powerful basis for genetic counseling and enhance our current understanding of the genetics factors for RP families.

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Dataset Information

Clinical and genetic analysis of 7 Chinese patients with ?-ureidopropionase deficiency.

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Clinical and genetic analysis of 7 Chinese patients with β-ureidopropionase deficiency.

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