No abstract

Wilson disease (WD) is an autosomal recessive disorder of copper metabolism. The gene responsible for WD was discovered in 1993 and is located on chromosome 13 at 13q14.3. It encodes a copper-specific transporting P-type ATPase. Early diagnosis can improve treatment outcome and decrease the rate of disability or even mortality.We used Sanger sequencing to identify mutation hot spots in 55 northern Vietnamese with a clinical diagnosis of WD. Mutations were screened and detected by direct DNA sequencing. A total of 26 different ATP7B gene mutations were identified, including seven novel mutations (five nonsense and two missense mutations). The most frequent mutations were p.Ser105Ter (24.55%), p.Arg778Leu (5.45%) and p.Thr850Ile (4.55%). Mutation detection rate in exon 2 was 34.55% and ranked first, followed by exon 8 with 16.36%, and exon 18 with 10.91% each, thus, exons 2, 8 and 18 are the mutation hot spots for northern VietnameseWD patients. These findings were different from previous studies in Asia. Our research established a suitable strategy for ATP7B gene testing in northern Vietnamese WD patients.

The sequence polymorphism of mitochondrial DNA (mtDNA) hypervariable Segment 1 (HV1) and hypervariable Segment 2 (HV2) are studied and applied to genetic diversity and human evolution assessment, forensic genetics, consanguinity determination, and mitochondrial disease diagnosis. Nucleotide sequence variations in HV1 and HV2, two hypervariable segments of the noncoding control region of human mitochondrial DNA (mtDNA), in selected ethnics of the Vietnamese population were elucidated through sequencing. In this study, we define the variations of HV1 and HV2 of 517 unrelated Vietnamese individuals in Kinh, Muong, Cham, and Khmer ethnic. We found 50 haplogroups: F1a haplogroup frequency is the highest at 15.7%; B5a haplogroup frequency is 10.8%, M haplogroup frequency is 8.9%, M7b1 haplogroup frequency is 7.7%; B6, D4e, D5a, E, F1c, F2a, F3a, G2a, M9b, N, N21 and U5a haplogroup frequencies are the lowest (1%). The frequency of SNP A263G are 100%; A73G is 99.6%, 315insC is 96%; 309insC is 56%; C16223T is 41%, and T16189C is 39%. We have assessed the genetic polymorphism of mtDNA HV1 and HV2 of 517 Kinh, Muong, Cham, Khmer ethnic samples.