Variation of Mitochondrial DNA HV1 AND HV2 of the Vietnamese Population.

BACKGROUND: The sequence polymorphism of mitochondrial DNA (mtDNA) hypervariable segment 1 (HV1) and hypervariable segment 2 (HV2) is studied and applied to genetic diversity and human evolution assessment, forensic genetics, consanguinity determination, and mitochondrial disease diagnosis. METHODS: The study identified the variations of HV1 and HV2 of 517 unrelated Vietnamese individuals in Kinh, Muong, Cham, and Khmer ethnic. We performed sequencing of two hypervariable segments of mitochondrial DNA: HV1 and HV2. RESULTS: Fifty haplogroups were identified in which F1a haplogroup frequency was highest at 15.7%, followed by B5a (10.8%), M (8.9%), and M7b1 (7.7%). The most frequently encountered SNPs in this study were A263G (100%), A73G (99.6%), 315insC (96%), 309insC (56%), C16223T (41%), and T16189C (39%). The genetic diversity was calculated at 99.83%, and the probability of random match of two individuals sharing the same mtDNA haplotype was 0.37%. CONCLUSION: We have assessed the genetic polymorphism of mtDNA HV1 and HV2 of 517 Kinh, Muong, Cham, and Khmer ethnic samples. The result will help in better understanding of Vietnamese's mitochondrial genome diversity and aid in population as well as forensic science.

Acromesomelic dysplasia Maroteaux-type in patients from Vietnam.

Acromesomelic dysplasias are rare skeletal disorders leading to severe short stature and abnormal skeletal morphology. Acromesomelic dysplasia Maroteaux-type is caused by homozygous or compound heterozygous pathogenic variants in NPR2 that encodes for natriuretic peptide receptor B. Here, we reported the first AMDM case in South East Asia and identified a novel pathogenic variant in NPR2 (c. 152T>C, p. (Leu51Pro)). Further analyses reveal the parents and two other family members were heterozygous for the variant. The clinical report highlights the importance of molecular genetic testing in diagnosing rare hereditable disease affecting skeletal abnormalities.

Method of delivery and pregnancy outcomes in Asia: the WHO global survey on maternal and perinatal health 2007-08.

BACKGROUND: There has been concern about rising rates of caesarean section worldwide. This Article reports the third phase of the WHO global survey, which aimed to estimate the rate of different methods of delivery and to examine the relation between method of delivery and maternal and perinatal outcomes in selected facilities in Africa and Latin America in 2004-05, and in Asia in 2007-08. METHODS: Nine countries participated in the Asia global survey: Cambodia, China, India, Japan, Nepal, Philippines, Sri Lanka, Thailand, and Vietnam. In each country, the capital city and two other regions or provinces were randomly selected. We studied all women admitted for delivery during 3 months in institutions with 6000 or fewer expected deliveries per year and during 2 months in those with more than 6000 deliveries. We gathered data for institutions to obtain a detailed description of the health facility and its resources for obstetric care. We obtained data from women's medical records to summarise obstetric and perinatal events. FINDINGS: We obtained data for 109 101 of 112 152 deliveries reported in 122 recruited facilities (97% coverage), and analysed 107 950 deliveries. The overall rate of caesarean section was 27.3% (n=29 428) and of operative vaginal delivery was 3.2% (n=3465). Risk of maternal mortality and morbidity index (at least one of: maternal mortality, admission to intensive care unit [ICU], blood transfusion, hysterectomy, or internal iliac artery ligation) was increased for operative vaginal delivery (adjusted odds ratio 2.1, 95% CI 1.7-2.6) and all types of caesarean section (antepartum without indication 2.7, 1.4-5.5; antepartum with indication 10.6, 9.3-12.0; intrapartum without indication 14.2, 9.8-20.7; intrapartum with indication 14.5, 13.2-16.0). For breech presentation, caesarean section, either antepartum (0.2, 0.1-0.3) or intrapartum (0.3, 0.2-0.4), was associated with improved perinatal outcomes, but also with increased risk of stay in neonatal ICU (2.0, 1.1-3.6; and 2.1, 1.2-3.7, respectively). INTERPRETATION: To improve maternal and perinatal outcomes, caesarean section should be done only when there is a medical indication. FUNDING: US Agency for International Development (USAID); UNDP/UNFPA/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), WHO, Switzerland; Ministry of Health, Labour and Welfare of Japan; Ministry of Public Health, China; and Indian Council of Medical Research.

Comparison of vaginal and sublingual misoprostol for second trimester abortion: randomized controlled equivalence trial.

BACKGROUND: To identify an effective misoprostol-only regimen for the termination of second trimester pregnancy, we compared sublingual and vaginal administration of multiple doses of misoprostol in a randomized, placebo-controlled equivalence trial. METHODS: Six hundred and eighty-one healthy pregnant women requesting medical abortion at 13-20 weeks' gestation were randomly assigned within 11 gynaecological centres in seven countries into two treatment groups: 400 microg of misoprostol administered either sublingually or vaginally every 3 h up to five doses, followed by sublingual administration of 400 microg misoprostol every 3 h up to five doses if abortion had not occurred at 24 h after the start of treatment. We chose 10% as the margin of equivalence. The primary end-point was the efficacy of the treatments to terminate pregnancy in 24 h. Successful abortion within 48 h was also considered as an outcome along with the induction-to-abortion-interval, side effects and women's perceptions on these treatments. RESULTS: At 24 h, the success (complete or incomplete abortion) rate was 85.9% in the vaginal administration group and 79.8% in the sublingual group (difference: 6.1%, 95% CI: 0.5 to 11.8). Thus, equivalence could not be concluded overall; the difference, however, was driven by the nulliparous women, among whom vaginal administration was clearly superior to sublingual administration (87.3% versus 68.5%), whereas no significant difference was observed between vaginal and sublingual treatments among parous women (84.7% versus 88.5%). The rates of side effects were similar in both groups except for fever, which was more common in the vaginal group. About 70% of women in both groups preferred sublingual administration. CONCLUSIONS: Equivalence between vaginal and sublingual administration could not be demonstrated overall. Vaginal administration showed a higher effectiveness than sublingual administration in terminating second trimester pregnancies, but this result was mainly driven by nulliparous women. Fever was more prevalent with vaginal administration. Registered with International Standard Randomized Controlled Trial number ISRCTN72965671.

Assessment of 6 STR loci for prenatal diagnosis of Duchenne Muscular Dystrophy.

OBJECTIVE: Duchenne Muscular Dystrophy is an X-linked recessive disorder characterized by progressive muscular degeneration, patients often develop cardiac failure in the later stage and death occurs before 20 years of age. For a disease with poor postnatal prognosis such as Duchenne Muscular Dystrophy (DMD), providing the carrier mother with the option of prenatal diagnosis in a subsequent pregnancy is accepted practice in many places where termination of pregnancy is allowed. Though methods of direct sequencing such as Sanger's sequencing has been widely used, Next-Generation Sequencing is been increasingly replacing most of its application. For the DMD gene, being the longest gene in the human genome, methods of direct sequencing is often unpractical and time-consuming, instead, STR analysis for linkage analysis would be a cost-effective option and have been used routinely for prenatal diagnosis of DMD. The diagnostic significance of the STRs is based on several criteria, the most important one being the heterozygosity of the locus, power of discrimination (PD) and power of exclusion (PE). MATERIAL AND METHODS: In this study, we investigated the feasibility of application and diagnostic value of 6 STR loci (DSTR49, DSTR50, DXS1036, DXS1067, DXS890, DXS9907) in the proximity of the DMD gene, 66 healthy individuals were recruited for STR analysis and 5 cases of prenatal diagnosis for carrier mother were performed. RESULT: Allele frequency, heterozygosity, polymorphic information content, the power of discrimination and exclusion and Hardy-Weinberg equilibrium were analyzed and calculated for the 6 STR loci. 5 of these loci (DSTR49, DSTR50, DXS1067, DXS890, DXS9907) were found practical and useful for preimplantation Genetic diagnosis (PGD) and prenatal diagnosis. All 5 cases of prenatal diagnosis using the method had informative STR results and correct diagnosis. CONCLUSION: We concluded that our protocol of STR analysis can be applied for prenatal diagnosis and pre-implantation genetic diagnosis of DMD with high confidence and accuracy, especially in clinical settings where diagnostic resources are more limited.

Mosaicism in carrier of Duchenne muscular dystrophy mutation - Implication for prenatal diagnosis.

OBJECTIVE: Duchenne muscular dystrophy (DMD) is a severe disorder caused by mutation in the X-linked dystrophin gene, therefor carrier testing is required for all female family members. However, there are cases mutation analysis cannot detect any mutation due to a phenomenon called mosaicism. The case report describes a case of mosaicism in a DMD carrier and discusses the approach in diagnosis and counseling of familial disorder. CASE REPORT: The proband was diagnosed with DMD at age six. Sequencing of Dystrophin gene identified a 2-nucleotide deletion c.2032_2033delCA, p.Q678DfsX41. Family investigation suggested that the mother was an obligate carrier of Dystrophin mutation. Sequencing of DNA sample from the mother's peripheral blood did not reveal any mutation, there for we take sample from hair follicle for analysis. The result indicated that the mother was a carrier but was masked from initial analysis by mosaicsism. CONCLUSION: We suggested that more care need to be taken in identifying cases when no mutation was detected in probable or obligate carrier and prenatal diagnosis should remain an option.