Discussion on the standard of clinical genetic testing report and the consensus of gene testing industry / 中华医学遗传学杂志

The widespread application of next generation sequencing (NGS) in clinical settings has enabled testing, diagnosis, treatment and prevention of genetic diseases. However, many issues have arisen in the meanwhile. One of the most pressing issues is the lack of standards for reporting genetic test results across different service providers. The First Forum on Standards and Specifications for Clinical Genetic Testing was held to address the issue in Shenzhen, China, on October 28, 2017. Participants, including geneticists, clinicians, and representatives of genetic testing service providers, discussed problems of clinical genetic testing services across in China and shared opinions on principles, challenges, and standards for reporting clinical genetic test results. Here we summarize expert opinions presented at the seminar and report the consensus, which will serve as a basis for the development of standards and guidelines for reporting of clinical genetic testing results, in order to promote the standardization and regulation of genetic testing services in China.

Association study between candidate genes involved in cell-cell adhesion and non-syndromic cleft lip with or without cleft palate in Chinese population / 北京大学学报(医学版)

Objective:To explore the association and gene-environment interaction between single nu-cleotide polymorphisms (SNPs)involved in cell-cell adhesion and non-syndromic cleft lip with or without cleft palate (NSCL/P)among Chinese population.Methods:A total of 806 NSCL/P trios were drawn by an international consortium,which conducted a genome-wide association study (GWAS)using a case-parent trio design to investigate genes affecting risks to NSCL/P.The transmission disequilibrium test (TDT)was used to explore the association between cell-cell adhesion genes,including CDH1,CT-NNB1,PVRL1,PVRL2,PVRL3,ACTN1,VCL,LEF1,and NSCL/P.Conditional Logistic regression models were used to estimate effects on risk of exposed and unexposed children.Four common maternal exposures including maternal smoking,environmental tobacco smoke,alcohol consumption and multivita-min supplementation during pregnancy were included in this study.Results:A total of 226 SNP markers were tested after quality control in this study.Although 23 SNPs in three genes (CTNNB1,CDH1, ACTN1)showed nominal significant association with NSCL/P in the TDT (P 0.000 2).Tests for gene-environment interaction yielded significant results be-tween rs7431 27 in ACTN1 and environmental tobacco smoke (P =0.000 1 )with an estimated OR (case |G and E)=2.00(95%CI:1 .23 -3.26)and OR (case |G no E)=0.59 (95%CI:0.38 -0.90).Among the lower P value results in gene-environment tests,there were no significant results be-tween rs1 475034,rs370535,rs227341 9 in ACTN1,rs1 06871 in CTNNB1 and environmental tobacco smoke interaction.There were also no significant results between rs7634000,rs2971 366,rs2634553, rs1 489032,rs762481 2 in PVRL3 and multivitamin supplementation during pregnancy in gene-environ-ment tests(P >0.000 2).Conclusion:There is no association between cell-cell adhesion genes,inclu-ding CDH1,CTNNB1,PVRL1,PVRL2,PVRL3,ACTN1,VCL,LEF1,and NSCL/P when the genes are considered alone.But our results suggest that SNPs in ACTN1 may influence the risk to NSCL/P through gene-environment interaction.

A novel indel NF1 mutation identified in a patient with neurofibromatosis type 1 / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the genetic etiology in a Chinese patient with neurofibromatosis type 1 (NF-1).</p><p><b>METHODS</b>All coding exons and the flanking sequences of neurofibromin 1 (NF1) gene from the patient were captured, individually barcoded and subjected to HiSeq2000 high-throughput sequencing. Suspected mutation was validated in the nuclear family members with Sanger sequencing.</p><p><b>RESULTS</b>A novel indel mutation, c.789_790delAGinsT, was identified in the exon 8 of the NF1 gene in the patient but not in her asymptomatic parents. The mutation was predicted to have caused shifting of the reading frame and a premature downstream stop codon (p.K263Nfs*18). Two known polymorphisms, c.888+108 C>T (rs2953000) and c.888+118 G>T (rs2952999), was detected in the flanking of the indel mutation in the patient and her father. Sequencing chromatogram for the family indicates that above changes are located on the same chromosome.</p><p><b>CONCLUSION</b>The c.789_790delAGinsT, as a de novo mutation occurring on the paternally derived chromosome, is most likely to be causative for the disease. Compared with Sanger sequencing, targeted next-generation sequencing is more efficient and can dramatically reduce the cost for the genetic testing of NF-1.</p>

The mutation analysis of PAH gene and prenatal diagnosis in classical phenylketonuria family / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To characterize the mutation spectrum of phenylalanine hydroxylase (PAH) gene and perform prenatal diagnosis for families with classical phenylketonuria.</p><p><b>METHODS</b>By stratified sequencing, mutations were detected in the exons and flaking introns of PAH gene of 44 families with classical phenylketonuria. 47 fetuses were diagnosed by combined sequencing with linkage analysis of three common short tandem repeats (STR) (PAH-STR, PAH-26 and PAH-32) in the PAH gene.</p><p><b>RESULTS</b>Thirty-one types of mutations were identified. A total of 84 mutations were identified in 88 alleles (95.45%), in which the most common mutation have been R243Q (21.59%), EX6-96A>G (6.82%), IVS4-1G>A (5.86%) and IVS7+2T>A (5.86%). Most mutations were found in exons 3, 5, 6, 7, 11 and 12. The polymorphism information content (PIC) of these three STR markers was 0.71 (PAH-STR), 0.48 (PAH-26) and 0.40 (PAH-32), respectively. Prenatal diagnosis was performed successfully with the combined method in 47 fetuses of 44 classical phenylketonuria families. Among them, 11 (23.4%) were diagnosed as affected, 24 (51.1%) as carriers, and 12 (25.5%) as unaffected.</p><p><b>CONCLUSION</b>Prenatal diagnosis can be achieved efficiently and accurately by stratified sequencing of PAH gene and linkage analysis of STR for classical phenylketonuria families.</p>

Detection of NPM1 gene mutation in acute myeloid leukemia / 中华检验医学杂志

Objective To analyze the frequency of NPM1 mutation in de novo acute myeloid leukemia (AML) patients and the relationship between NPM1 mutation and chromosome alterations,as well as FAB subgroups,and to analyze the mutation type.MethodsA total of 99 de novo AML patients from 2004 to 2010 in China-Japan Friendship Hospital were studied.Genomic DNA was amplified by polymerase chain reaction (PCR),denaturing polyacrylamide gel electrophoresis (PAGE) and capillary electrophoresis were used to detect the mutation of NPM1 gene in 99 AML patients,and karyotyping was performed in 72 AML patients by G banding techniques.DNA sequences analysis of NPM1 mutation was performed on 10 patients.Chi-square test was used to compare the frequencies of NPM1 mutation among the different subgroups,and McNemar's test was used to compare the different rates between denaturing PAGE and capillary electrophoresis.ResultsThe frequencies of NPM1 mutations were detected in 15％ (15/99) of AML patients with capillary electrophoresis and 11％ (11/99 ) with denaturing PAGE(x2 =2.25,P ＞0.05 ).The NPM1 was at different rates in M2(27％,8/30),M5(32％,6/19),M6( 13％,1/8),respectively (x2 =1.06,P ＞ 0.05 ),and not detected in the other subgroups.NPM1 mutation in patients with normal karyotype(26％ ) was more prevalent than patients with abnormal karyotype (4％) (x2 =5.61,P ＜ 0.05)All of the 10 patients were of A type ( c.860_863dupTCTG).The C-terminal portion of the NPM protein by replacing the last seven amino acids(WQWRKSL) with 11 residues (CLAVEEVSLRK).Two intronic deletions were novel,one case was IVS10-18_-15delCTTT,the other was IVS10-17_-15delTTT.Conclusions NPM1 mutations represents a common genetic abnormality in AML patients,and NPM1 mutation in patients with normal karyotype is higher than patients with abnormal karyotype.Two new intronic deletion mutations are identified.

New multiplex-PCR assay for detection of deletions of DMD gene in Chinese DMD patients / 中华检验医学杂志

Objective To establish a new multiplex-PCR assay to improve the detection rate of mutations in the DMD gene in Chinese patients. Methods A retrospective review of DMD deletion spectrum of 355 DMD patients with deletions all over the gene was performed. All deletions were confirmed by " one-step approach" diagnostic procedure and MLPA analysis. The exons with high frequency of mutations were identified to constitute the amplification system and the PCR conditions were optimized. Results Two new multiplex-PCR assays were established. Assay one was used to detect 10 exons including exon 5, 8, 17, 44, 45, 47, 49, 50, 51 and 52 of DMD gene, in two PCR sets. The theoretical detection rate would be 92% (326/355). Assay two was used to detect 5 exons including exon 12, 19, 35, 43 and 54, which could be used to screen additional 5% (17/355) deletion cases. The method was validated in other 22 DMD patients. Multiplex-PCR results were completely identical to the MLPA results in all 22 DMD patients. Conclusions The two multiplex-PCR assays were established based on the analysis of 355 Chinese DMD patients with gene deletions. It is believed that the new approach would be more applicable for deletion detection on the Chinese DMD patients since the DMD cases involved were from the whole country.

Rapid detection of common ATP7B mutations in Wilson disease by high resolution melting analysis / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect the most prevalent mutations, R778L and P992L of ATP8B gene, in Chinese Wilson disease(WD) patients by high resolution melting (HRM) analysis after polymerase chain reaction (PCR).</p><p><b>METHODS</b>Genomic DNA was extracted from peripheral blood samples obtained from 30 cases of WD by the standard phenol/chloroform method. DNA fragments encompassing ATP7B exons 8 and 13 were produced by PCR amplification. The amplicons containing the R778L or P992L mutations were then generated by nested PCR. The nested PCR products were subjected to HRM analysis using the HR-1 instrument. Mutations detected in HRM analysis were verified by restriction analysis using restriction enzyme (MspI or AluI or AfaI) or DNA sequencing.</p><p><b>RESULTS</b>HRM analysis of the fragments encompassing ATP7B exon 8 showed four curve patterns. Subsequent restriction analysis and DNA sequencing proved that the four different curves represent four different genotypes: the wild type, the R778L/R778L homozygote, the R778L heterozygote, and the R778L/752.33delG compound heterozygote. Three HRM curve patterns were observed for the fragments encompassing ATP7B exon 13, representing the wild type, the P992L heterozygote, and the P992L/S975Y compound heterozygote. In our studied samples, allele frequencies of the R778L, P992L and S975Y mutations were 25%, 15% and 1.67%, respectively.</p><p><b>CONCLUSION</b>HRM analysis is a simple, accurate and sensitive approach for rapid detection of the ATP7B mutations and could be used as an optimized method for genetic testing in WD.</p>

Treatment of 2 children with mucopolysaccharidosis by allogeneic hematopoietic stem cell transplantation / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>Mucopolysaccharidosis(MPS) is a congenital hereditary disease. Only a few patients with this disease can be controlled by enzyme replacement therapy. Most of them are short of effective interference. To exploit the effect of treatment with allogenic hematopoietic stem cell transplantation, two children were treated with the transplantation.</p><p><b>METHODS</b>The two patients included a 23 month MPS-IH and an 18 month old MPS-VI at the time of transplantation. Busulfan of 20 mg/kg plus 200 mg of Cyclophosphamide were used as the conditioning regimen. Peripheral stem cells were collected from a 9/10 high resolution matched unrelated donor and a matched sibling carrier donor, respectively. The heart and lung were affected in the patient with MPS-IH. Medium obstructed pulmonary impairment was found by pulmonary function test at the time of transplantation. Medium mitral valve countercurrent and patent ductus arteriosis(PDA) were found by Doppla examination.</p><p><b>RESULTS</b>The number of hematopoietic stem cells was comparative between the two donors with total nucleated cells and CD34+ cells of 11 x 10(8)/kg and 17 x 10(8)/kg, and 7.6 x 10(6)/kg and 7.2x 10(6)/kg respectively. Neutrophil engrafted at day 11. The process of transplantation in the MPS-VI patient went smoothly with grade II graft versus host disease(GVHD) briefly and only 1 U RBC and 2 U platelet were transfused. For the MPS-IH patient, the process of transplantation was tough with platelet reaching to 20 x 10(9)/L till day 40 and 5 U RBC and 7 U platelet were transfused during transplantation. Grade III GVHD was resolved by steroid, mycophenolate mofetil (MMF) and CD25 antibody. Pneumonia recurred 3 times with 2 times rescued by trachea intubation and mechanical ventilation because of accompanying acute heart failure. At day 14 the lymphocytes in both patients were 100% from donors as evidenced by short tandem repeat-PCR(STR-PCR). MPS associated enzyme activity was increased to 70 nmol/h.mg and 66 nmol/h.mg at 3 month and still remained 50.9 nmol/h.mg and 44.5 nmol/h.mg at 2 years post transplantation. Till now the 2 patients have been followed up for 25 months and 28 months with good general condition. The cardiac and pulmonary functions have improved obviously in the MPS-IH patient. The cornea became clear in this patient.</p><p><b>CONCLUSION</b>Allogeneic hematopoietic stem cell transplantation is an effective measure to treat patient with MPS-IH and MPS-VI. Transplantation at earlier stage of age can decrease transplant related complications. It requires longer time follow up for observing the clinical effects for these patients.</p>

A Simplified Approach for Detecting Homologous Deletion of SMN1 Genes in Spinal Muacular Atrophy / 医学研究杂志

Objective To develop a rapid,reliable and convenient approach for diagnosing the homozygous deletion of SMN1 gene.Methods SMN1 gene was amplified specifically with double allele-specific PCR(AS-PCR).Meanwhile,one inrelevant gene was amplified as internal control by PAGE and agarose gel electrophoresis analysis to determine whether the sick children were with homozygous deletion of SMN1 genes.Results The homozygous deletion of exon7 in SMN1 gene was identified by agarose gel electrophoresis or PAGE accurately.Conclusion Compared to PCR-RFLP and DHPLC used in the past,this approach can diagnose homozygous deletion of SMA much more accurate,easier and more convenient without completed following analyses.

A Novel Mutation of ADAR Gene Identified in a Chinese Pedigree with Dyschromatosis Symmetrical Hereditaria / 医学研究杂志

Objective To discover the mutation of ADAR gene in a pedigree with dyschromatosis symmetrical hereditaria(DSH). Methods We investigated this family and collected blood samples of the individuals in this family. Mutation screening was carried out by PCR and direct sequencing. The allele specific primer was designed for the mutation point, and allele-specific PCR was carried out on the patients, normal family members and 40 normal individuals. Results A single nucleotide deletion (c.1642 delC) was identified in exon3 of ADAR gene in the patients of this family. This mutation was not detected in the normal family members and in any of the control individuals. Conclusion This single nucleotide deletion was responsible for the disease in the family.

Tumor necrosis factor ?-308 alleles in myasthenia gravis / 中华神经科杂志

Objective To analyze the associations between alleles of TNF?-308 and myasthenia gravis(MG) and its subgroups. Methods A biallelic polymorphism at position -308 in the promoter region of TNF? was screened by polymerase chain reaction (PCR) amplification and NcoⅠ restricted enzyme. One hundred MG patients and one hundred healthy controls of Chinese were analysed. Results The allele TNF?2(A) was found significantly increased in all patients (0.32 in MG vs 0.21 in healthy controls, P0.05), showing a trend of increase in patients with an late onset of disease (0.34) compared to age matched healthy controls (0.10, P

History of medical genetics in China / 北京大学学报(医学版)

As the completion of human genome project, application of the knowledge and techniques developed during thpast decade to the medical practice become more and more important and gain more and more attention. It is worthwhile to look back to the step prints of the development of medical genetics in China.1 The sprout of genetics in ChinaIt should be mentioned fromthe very beginning of the birth of the genetics in China to understand the historymedical genetics in China. In 1922, C.CHEN (Zhen CHEN) opened genetic courses in National Southeast Unversity after he returned from the T.H.MORGAN’s lab at Columbia University. He used Goldfish as a model fogenetic study. The Chinese scholars started their work on human genetics by survey the frequency of ABO bloogroup in the Chinese. Their result was published in1918. This was the first data of gene frequency of Chinese population, followed by reports on the inherited disease in Chinese on the frequency of color blindness in 1937. I1948, T. C. HSU described the ability to fold up the tip of the tongue as a recessive trait (MIM189300)[1,2]C.C.LI (Ching Chun LI) wrote a book,Introduction to Population Genetics, which became a wellknown book ithe world and from which a whole generation of geneticists benefited.

The relationship between nonresponse to hepatitis B vaccine and HLA genotype/haplotype / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study the relationship between the nonresponse to hepatitis B vaccine and HLA genotype/heplotype in Chinese population and provide the evidence for explaining the genetic mechanism of this nonresponse.</p><p><b>METHODS</b>Our research focused on the relationship between nonresponse to Hepatitis B vaccine and HLA-DRB1, DRB3, DRB4, DRB5 and DQB1 genotype/haplotype in Chinese population, collected from a community in Guangxi Zhuang Autonomous Region. The group specific amplification was employed to characterize 107 individuals' genotype and haplotype of HLA clusters. Different models statistics such as relative risk test, correlation test and linkage disequilibrium analysis were used to analyze the data.</p><p><b>RESULTS</b>The results showed that there is a linkage disequilibrium between nonresponse to Hepatitis B vaccine and HLA haplotype DR4, 1122 (DRB1 * 0401- 22, 1122)-DR53 (DRB4 * 0101101, 0102/3)-DQB4 (DQB1 * 04).</p><p><b>CONCLUSION</b>In Chinese population, nonresponse to hepatitis B vaccine is highly associated with special HLA haplotye.</p>

SCREENING FOR PHENYLKETONURIA GENE MUTATION BY DNA AMPLIFICATION WITH THE POLYMERASE CHAIN REACTION / 西安交通大学学报(医学版)

Exon 3 termination mutation of phenylalanine hydroxylase (PAH) gene, the only identified one causing classical phenylketonuria (PKU) in Chinese, was detected in fourteen PKU children from Xi'an. The genomic DNA from these patients was amplified by polymerase chain reaction(PCR) and dot hybridied with specific oligonucleotide probes. This mutation is not present in any of these affected children, which indicates that phenylketonuria in Chinese may be caused by other mutations in phenylalanine hydroxylase locus. PCR amplification combining with oligonucleotide dot hybridization is technically feasible for prenatal diagnosis and carrier screening for PKU.