Published in:
Open Access
01-12-2018 | Case report
Identification and characterization of a novel 43-bp deletion mutation of the ATP7B gene in a Chinese patient with Wilson’s disease: a case report
Authors:
Gang Liu, Dingyuan Ma, Jian Cheng, Jingjing Zhang, Chunyu Luo, Yun Sun, Ping Hu, Yuguo Wang, Tao Jiang, Zhengfeng Xu
Published in:
BMC Medical Genetics
|
Issue 1/2018
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Abstract
Background
Wilson’s disease (WD) is an autosomal recessive disorder characterized by copper accumulation. ATP7B gene mutations lead to ATP7B protein dysfunction, which in turn causes Wilson’s disease.
Case presentation
We describe a male case of Wilson’s disease diagnosed at 10 years after routine biochemical test that showed low serum ceruloplasmin levels and Kayser–Fleischer rings in both corneas. Analysis of the ATP7B gene revealed compound heterozygous mutations in the proband, including the reported c.3517G > A mutation and a novel c.532_574del mutation. The c.532_574del mutation covered a 43-bp region in exon 2, and resulted in a frameshift mutation (p.Leu178PhefsX10). By base sequence analysis, two microhomologies (TCTCA) were observed on both deletion breakpoints in the ATP7B gene. Meanwhile, the presence of some sequence motifs associated with DNA breakage near the deletion region promoted DNA strand break.
Conclusions
By comparison, a replication-based mechanism named fork stalling and template switching/ microhomology-mediated break-induced replication (FoSTeS/MMBIR) was used to explain the formation of this novel deletion mutation.