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Hemophilia A (HA) is an X-linked recessive bleeding disease caused by a deficiency or dysfunction of blood coagulation factor VIII (FVIII). Available treatment to replenish the missing factor may not reach a good outcome for all patients because of potential complications that include the development of inhibitor antibodies directed against factor VIII. Therefore, the prevention of transmitting pathogenic mutations to the next generation is the best solution for this disease. Preimplantation genetic testing for a monogenic disorder (PGT-M) has become a standard method to prevent the transmission of monogenic heritable disease. The gold standard of the molecular technique used for PGT-M nowadays is the co-amplification of the polymorphic microsatellite linkage markers that use microsatellite DNA technique that overcomes the limitation of other methods. The important issue of this technique is the definition of markers that are specific for each allele on different loci. Each gene locus needs a characteristic design to allow accurate diagnosis that can be applied on PGT-M due to the limited quantity of DNA available. Here we present our study of four specific self-designed linked polymorphic markers applied on screening the embryos before implantation for hemophilia A families in Vietnam.In this study, we investigated the feasibility of application and diagnostic value of 4 STR loci (FXS1108, DXS9897, F8int22, DXS9901) in the intragenic or neighbouring regions of the F8 gene. 35 hemophilia A families were recruited for STR analysis to define at least two characteristic heterologous markers for each family and 12 cases of pre-implantation genetic testing (PGT-M) for carrier mothers were performed.All 4 of these loci (FXS1108, DXS9897, F8int22, DXS9901) were found practical and useful for preimplantation genetic testing (PGT-M). All 12 cases of PGT-M using the method had informative STR results and correct diagnosis was achieved. 9 out of the 12 mothers (75%) were implanted with 1-2 thawed embryos after the biopsy resulting in the birth of 5 healthy babies (55%).We conclude that specific 4 STR markers for rapid pre-implantation genetic testing of hemophilia A can be successfully applied with high confidence and accuracy in clinical settings. The results of the study provide solid evidence confirming that the microsatellite DNA technique is a highly reliable method, suitable for hemophilia A families wishing to determine carrier status or having healthy babies.

BackgroundHarlequin ichthyosis (HI) is a severe rare genetic disease that mainly affects the skin. Neonates with this disease are born with thick skin and large diamond-shaped plates covering most of their bodies. Affected neonates lose the ability to control dehydration and regulate temperature and are more susceptible to infections. They also face respiratory failure and feeding problems. These clinical symptoms are factors associated with high mortality rates of neonates with HI. Until now, there are still no effective treatments for HI patients and most patients die in the newborn period. Mutation in the ABCA12 gene, which encodes an adenosine triphosphate-binding cassette (ABC) transporter, has been demonstrated as the major cause of HI.Case presentationIn this study, we report the case who is one infant that was born prematurely at 32 gestational weeks with the whole body covered with thick plate-like scales of skin. The infant was severely infected with mild edema, multiple cracked skins full of the body, yellow discharge, and necrosis of fingers and toes. The infant was suspected to be affected by HI. Whole exome sequencing (WES) was performed as a tool for detecting the novel mutation in one prematurely born Vietnam infant with HI phenotype. And after that, the mutation was confirmed by the Sanger sequencing method in the patient and the members of his family. In this case, one novel mutation c.6353C > G (p.S2118X, Hom) in the ABCA12 gene, was detected in the patient. The mutation has not been reported in any HI patients previously. This mutation was also found in a heterozygous state in the members of the patient's family, including his parents, an older brother, and an older sister who are no symptoms.ConclusionsIn this study, we identified a novel mutation in a Vietnamese patient with HI by whole exome sequencing. The results for the patient and the members of his family will be helpful in understanding the etiology of the disease, diagnosing carriers, assisting in genetic counseling, and emphasizing the need for DNA-based prenatal screening for families with a history of the disease.

Objective MCPH (microcephaly primary hereditary) is a group of autosomal recessive developmental disorders with microcephaly present at birth and intellectual disability. Since a second trimester ultrasound is not able to detect subtypes with minimal prenatal presentations, only prenatal diagnosis by genetic testing can confirm these cases and allow for effective genetic counseling, especially a family with a previously affected child. Case Report A 37-year-old women was pregnant for the third time and had two prior children with profound microcephaly and mental retardation. Targeted panel sequencing identified novel compound heterozygous ASPM pathogenic variants: c.1615_1616del (p. Glu539ArgfsTer15); c.∗293T > A (p. Leu98Ter), which confirmed the diagnosis of MCPH5 (#OMIM 608716). Genetic testing was conducted for family members and applied on prenatal diagnosis. Conclusion This is the first cases of MCPH5 to be reported in Vietnam and the genetic result aided in prenatal diagnosis of a high-risk pregnancy. The study highlights the importance of genetic testing in defining definitive diagnosis which allowed for timely prenatal diagnosis and genetic counseling for the family.

Ovarian cancer is one of the most common gynecological malignancies. The gene RAD51involves homologous recombinational repair for double-strand breaks of DNA, so its polymorphisms and mutations are associated with cancer risk. The authors studied, by using a case-control design, whether single nucleotide polymorphism rs1801321 of RAD51 gene associated with ovarian cancer risk among Vietnamese females. Sample sets included 380 ovarian cancer cases and 380 healthy controls of similar age distribution. The genotypes of rs1801321 polymorphism were determined using the Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The distribution of genotype GG, GT, TT was 55.3, 29.2, 15.5% for the patients group and 47.9, 41.8, 10.3% for the control group, respectively (p=0.001). The RAD51 rs1801321 polymorphism was associated with the risk of ovarian cancer among Vietnamese females.

Background: Hypertrophic Cardiomyopathy (HCM) is one of the leading causes of sudden cardiac death in adults.HCM is inherited in an autosomal dominant manner; however, the genetic etiology of the disease is not fully explained and studies on the hereditary characteristics in family trees are still underway. Methods: Ten HCM patients and 31 of their relatives were recruited. Targeted sequencing for 4 HCM related-genes, including MYH7, MYBPC3, TNNT2, and TNNI3, using targeted next-generation sequencing (NGS) was carried out. Demographic, clinical, electrocardiography, and echocardiography characteristics were also characterized. Results: Among the 10 HCM patients, 5 were identified with the HCM pathogenic variants in MYH7 (3 patients), MYBPC3 (1 patient), and TNNT2 (1 patient) genes. Eleven out of 31 relatives from these 5 genotype-positive patients carried the same pathogenic variants. We found the novel c.822-2 A>G variant in the splicing site of the TNNT2 gene responsible for HCM disease in a family with 7 subjects genotype positive and 3 others who suffered from sudden cardiac death. Conclusion: This case series highlighted the importance of genetic testing for clinically confirmed HCM patients and family members. The genetic information can be used as a molecular marker to complement the clinical presentation in the diagnosis of HCM, as well as a prognostic tool for the patients and their family members.

β-thalassemia is an autosomal recessive disease with the reduction or absence in the production of β-globin chain in the hemoglobin, which is caused by mutations in the Hemoglobin subunit beta (HBB) gene. In Vietnam, the number of β-thalassemia carriers range from 1.5 to 25.0%, depending on ethnic and geographical areas, which is much higher than WHO’s data worldwide (1.5%). Hence, preimplantation genetic diagnosis (PGD) plays a crucial role in reducing the rate of β-thalassemia affected patients/carriers. In this research, we report the feasibility and reliability of conducting PGD in combination with the use of short tandem repeat (STR) markers in facilitating the birth of healthy children. Six STRs, which were reported to closely linked with the HBB gene, were used on 15 couples of β-thalassemia carriers. With 231 embryos, 168 blastocysts were formed (formation rate of 72.73%), and 88 were biopsied and examined with STRs haplotyping and pedigree analysis. Thus, the results were verified by Sanger sequencing, as a definitive diagnosis. Consequently, 11 over 15 couples have achieved pregnancy of healthy or at least asymptomatic offspring. Only three couples failed to detect any signs of pregnancy such as increased Human Chorionic Gonadotropin (HCG) level, foetal sac, or heart; and one couple has not reached embryo transfer as they were proposed to continue with HLA-matching to screen for a potential umbilical cord blood donor sibling. Thus, these results have indicated that the combination of PGD with STRs analysis confirmed by Sanger sequencing has demonstrated to be a well-grounded and practical clinical strategy to improve the detection of β-thalassemia in the pregnancies of couples at-risk before embryo transfer, thus reducing β-thalassemia rate in the population.

Aims Dozens of causative genes and their mechanisms of nonsyndromic cleft lip with or without cleft palate (NSCL/P) were revealed through genome‐wide association and linkage studies. Results were, however, not always replicated in different populations or methodologies. This study used case–control and family based approaches to investigate the etiology of NSCL/P and its two subtypes: nonsyndromic cleft lip only (NSCLO) and nonsyndromic cleft lip and palate (NSCLP) among the Vietnamese population. Methods Two hundred and seventeen NSCL/P case‐parent trios (one affected child and two parents), including 105 NSCLO and 112 NSCLP were involved for a family based design; and 273 ethnic and region‐matched healthy controls with no cleft history in their families were recruited for a case–control design. Three SNPs consisting of TFAP2A (rs1675414 and rs303048) and 8q24 (rs987525) were genotyped using the TaqMan SNP genotyping assay. Results TFAP2A rs1675414 was associated with NSCLO, replicated by both case‐control and family based tests. Other SNPs yielded no evidence of susceptibility to NSCL/P or two subtypes. Conclusion The current investigation suggests an intriguing role of TFAP2A in the etiology of NSCLO among the Vietnamese population., This study used case‐control and family‐based approaches to investigate the etiology of NSCL/P and its two subtypes: nonsyndromic cleft lip only (NSCLO), nonsyndromic cleft lip and palate (NSCLP) among Vietnamese population. TFAP2A rs1675414 was associated with NSCLO, replicated by both case‐control and family‐based tests.

Mục tiêu: Đánh giá mối liên quan giữa kiểu gen MTHFR C677T và A1298C với tình trạng sảy thai, thai chết lưu. Đối tượng và phương pháp: Nghiên cứu bệnh chứng 118 người trong đó 35 người nhóm chứng và 83 người nhóm có sảy thai, thai chết lưu ít nhất 2 lần. Xác định kiểu gen MTHFR C677T và A1298C của nhóm nghiên cứu bằng kỹ thuật Realtime PCR. Kết quả: Tỷ lệ đột biển của MTHFR C677T lần lượt là 43,4% và 31,4% trong nhóm bệnh và nhóm chứng. Tỷ lệ đột biến của MTHFR A1298C trong nhóm bệnh và nhóm chứng lần lượt là 53% và 34,3%. Tổ hợp của 2 đột biến MTHFR C677T và A1298C ỏ nhóm bệnh cao hơn đáng kể so với nhóm chứng với p

Background Lupus nephritis is a common complication of systemic lupus erythematosus (SLE, OMIM #15200) in the Asian population and a main contributor to mortality and morbidity. In this study, we evaluate the variants on three genes STAT4, CDKN1A, and IRF5 and their association with lupus nephritis. Method One hundred fifty‐two SLE patients with confirmed lupus nephritis (through biopsy) and 76 healthy controls were recruited. Genotyping of SNPs on three gene STAT4, CDKN1A, and IRF5, phenotypic, and laboratory assessment were performed; renal biopsy and classification were carried out for the patient group. Results Carriers of rs7582694 C alleles on STAT4 have higher risk of lupus nephritis (OR 2.0; 95% CI [1.14, 3.19]; p = 0.015), at higher risk of hematuria and higher serum level of dsDNA antibodies compared to controls (p, Despite the current evidence of genetic factor on the risk of Lupus Nephritis, there are currently no study assessing these variants in a Vietnamese population, and only a few studies have investigated the genotype‐phenotype correlation in Lupus Nephritis patients. Thus, in this report, we evaluate the polymorphisms of these three genes (STAT4, CDKN1A and IRF5) and their association with the phenotype of patients with Lupus nephritis. In which the disease progression was assessed with renal biopsy and careful clinical work‐up.

Autosomal recessive congenital ichthyosis is a heterogeneous group of congenital disorders characterized by aberrant skin cornification and diffuse skin scaling. Some patients with this condition are born encased in a collodion membrane which is later shed, revealing the underlying skin disorder. Self-healing collodion baby (SHCB) is a less common phenotype of this disorder, accounting for about 10% of the patients, in which the membrane peels after several weeks, leaving no underlying skin aberration. Here, we report and discuss the diagnosis and management of an infant with SHCB in Vietnam due to compound heterozygous pathogenic mutations in TGM1.

Recurrent pregnancy loss (RPL) is a physical and mental burden for women. In Vietnam, exploring the cause of miscarriages is still a challenge to clinical physicians. We aimed to investigate the etiology of RPL in the National Hospital of Obstetrics and Gynecology in Vietnam from 2012 to 2014. The cross-sectional study included 301 pregnant women with a history of RPL. The patients were examined and offered medical testing to determine the cause(s). Based on the testing, we determined causation for (11.29%) patients who had positive scores on an antiphospholipid antibody test and who were subsequently successfully treated for their problem.

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. Keywords: Duchenne muscular dystrophy, Dystrophin, Mosaicism, Counseling, Prenatal diagnosis

Mục tiêu: Xác định giá trị của DNA thai tự do (cell-free fetal DNAcffDNA) trong sàng lọc trước sinh không xâm lấn (Non-Invasive Prenatal Screening-NIPS) phát hiện lệch bội nhiễm sắc thể (NST) 21, 18, 13 và nhiễm sắc thể giới tính thai sử dụng công nghệ giải trình tự bán dẫn dựa vào phương pháp SeqFF. Đối tượng và phương pháp nghiên cứu: Nghiên cứu thực hiện trên 1231 mẫu máu thai phụ mang thai đơn, có tuổi thai từ 10 tuần thai thuộc nhóm nguy cơ cao mang thai lệch bội nhiễm sắc thể. DNA tự do trong huyết tương mẹ được giải trình tự đồng thời, số lượng lớn các đoạn ngắn nucleotid (massive parallel sequencing–MPS) và phân tích bằng thuật toán tin sinh. Kết quả nghiên cứu: cffDNA cao hơn có ý nghĩa thống kê giữa nhóm NIPS dương tính với trisomy 21 và 18 (12,55% và 10,55%) so với nhóm NIPS âm tính (7,5%). Có mối tương quan thuận có ý nghĩa giữa hệ số z-score và tỷ lệ cffDNA nhóm NIPS dương tính với trisomy 21, 18, 13 (p

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.

Inactivating mutations of the CYP21A2 gene, encoding for steroid synthesis, have been reported in patients with congenital adrenal hyperplasia (CAH). We report a case of an infant who were diagnosed with CAH and presented with the severe phenotype of CAH with symptoms such as increased testicular volume, elevated of 17-hydroxyprogesteron, testosterone and progesterone. In this study, we established an assay for the detection of unusual genetic in the CYP21A2 gene in the proband and his family. A novel nonsense mutation c.374C G which caused a substitutions of Serine for a stop codon at codon 125 (p.S125

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.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.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%.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.

Primary congenital glaucoma in Vietnam: analysis and identification of novel CYP1B1 variants

Background. Gastric cancer (GC) is one of the leading causes of cancer-related death in Vietnam. Research on health-related quality of life of Vietnamese gastric cancer patients is still in its infancy. Aim. To assess the health-related quality of life (HRQOL) of GC patients using the 15D instrument. Materials and Method. 182 Vietnamese gastric cancer patients were selected to be interviewed and their HRQOL was assessed using the generic 15D questionnaire. Tables regarding history, disease characteristics, and HRQOL of participants were formulated according to genders using STATA 12.0. Results. The average age of the participants was 60.8 ± 11.6. The average time from diagnosis to the date of interview was 14.8 ± 8.4 months. The health-related quality of life (HRQOL) index score of gastric cancer patients using the 15D instrument was 0.92 ± 0.08, in which the “sexual activity” dimension had the lowest score of 0.66. Also, our study found several factors affecting HRQOL, including age, occupation, education, disease stage, treatment, and time from the date of diagnosis. Conclusion. The 15D instrument was a suitable tool to assess Vietnamese gastric cancer patients’ quality of life. Findings from the study suggest the importance of frequently measuring personal functioning and performance of GC patients as parts of QOL assessment during clinical examination. It also implies the needs for more focused policies on raising the overall quality of life of patients such as encouragement of periodical HQROL assessment and acknowledging HRQOL as a treatment/intervention goal besides the 5-year survival rate.

Inactivating mutations of the CYP21A2 gene, encoding for steroid synthesis, have been reported in patients with congenital adrenal hyperplasia (CAH). We report a case of an infant who were diagnosed with CAH and presented with the severe phenotype of CAH with symptoms such as increased testicular volume, elevated of 17-hydroxyprogesteron, testosterone and progesterone. In this study, we established an assay for the detection of unusual genetic in the CYP21A2 gene in the proband and his family. A novel nonsense mutation c.374C > G which caused a substitutions of Serine for a stop codon at codon 125 (p.S125*) within exon 3 was found in the proband. Parental genotype studies confirmed carrier state in the father, but the mother showed a wild allele by PCR and sequencing. This inspired us to find deletions using multiplex ligation-dependent probe amplification (MLPA) technique. The probands were found to have a large deletion in exons 1 and 3, while the mother only had deletion in exon 1. Therefore, mutation c.374C > G (p.S125*) in the proband is considered as a heterozygous deletion. This mutation caused a truncated protein which lead to the salt wasting CAH phenotype of the proband. This novel nonsense mutation expands the CYP21A2 mutation spectrum in CAH disorder. This case also highlights the need of caution when interpreting results of molecular genetic testing during genetic counseling.

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.

The adipose tissue contains a large numbers of stem cells; adipose-derived stem cells (ADSCs) can be em- ployed in regenerative medicine. This study was aimed at isolating ADSCs and evaluating the safety of ADSCs in mouse models. Stromal vascular fraction (SVF) was collected from the adipose tissue using collagenase. ADSCs were then isolated from SVFs by in vitro culture. The stemness of the ADSCs was evaluated in vitro based on their self-renewal potential, po- tential to differentiate into osteoblasts, and adipocytes, and the expression of specific markers. Finally, the tumor forma- tion ability of ADSCs was evaluated in vivo in athymic mice. Results showed that 100% of the ADSC samples developed well and maintained homogeneity up to passage 10. The ADSCs were completely sterilized and could not form tumors in athymic mice. These initial results showed that ADSCs were safe for use in stem cell therapy.

Proteins with affinity to heparin under physiological conditions were isolated from bovine cerebral cortex. First, the extract of cerebral cortex was applied to a chondroitin polysulfate column under physiological conditions. Then, the pass-through fraction was applied to a heparin column. Among the bands on SDS polyacrylamide gel electrophoresis of the fraction bound to the heparin column, the major one was identified as fructose 1,6-bisphosphate aldolase (FPA), a cytosolic enzyme involved in the glycolytic pathway. The results indicated that FPA is a heparin-binding protein which exhibits no affinity to chondroitin polysulfate. The results of affinity chromatographies revealed that FPA binds to intact heparin and modified heparins desulfated at C2 OH of the iduronic acid residue or at C6 OH or C2 NH2 of the glucosamine residue. When 6-O-desulfated heparin was employed as the affinity ligand, a single peak having FPA activity was isolated from the extract of bovine cerebral cortex. By further Mono Q chromatography and Superdex gel-filtration, five isoenzymes were purified with more than 50% recovery. These isoenzymes were identified as FPA A4, A3C1, A2C2, A1C3, and C4 by native electrophoresis with and without 4 M urea and subsequent amino acid sequence analysis. The use of 6-O-desulfated heparin affinity chromatography thus facilitated the purification of FPA.

Heparin affinity chromatography of synthetic peptide fragments mimicking tissue factor pathway inhibitor (TFPI) indicated that the minimal heparin binding sequence consists of 12 amino acid residues located at the C-terminal tail. Within this minimal sequence, Arg-257 and Arg-259 appeared to contribute most significantly to interaction with heparin. Affinity chromatography of TFPI using immobilized heparin derivatives regiospecifically desulfated at O-6 of the glucosamine residue, N-2 of the glucosamine residue, and/or O-2 of the iduronic acid residue indicated that all the sulfate groups in heparin appeared to be required for TFPI-heparin interaction. Among them, however, the 6- O -sulfate groups appeared to make the largest contribution to the interaction, while the 2- O -sulfate groups contributed the least . In vitro experiments on the inhibition of factor Xa by TFPI enhanced with native and chemically modified heparins afforded similar results.