Objective To develop an efficient method for detecting the short tandem repeat(STR) of fetal DNA in maternal plasma by miniSTR technique.Methods A total of 9 blood samples form pregnant women from 11 to 27 weeks of gestation were collected.Each isolated total plasma DNA was amplified in single multiplex using the ABI MiniFilerTM kit,which could simultaneously genotype the 9 miniSTR loci,including D13S317,D7S820,D2S1338,D21S11,D16S539,D18S51,CSFIPO,FGA and Amelogenin,and the PCR products were detected by using ABI PrismTM 3100 DNA Sequencer.The allelic designation of each STR locus was accomplished using the GeneMapper ID 3.2 software.Results Father-origin fetal STR allele was detected in all the 9 plasma DNA samples.An average of 3.1 fetal STR alleles of the 8 autosomal STR loci was observed in each of the 9 plasma DNA samples.As for the Amelogenin locus,Amelogenin Y allele was detected in 5 plasma DNA samples from pregnancies with male fetus,and allelic peak height values were all over 50 RFU,according to ABI Mini FilerTM PCR conditions,and the ratio of Amelogenin Y allele peak height value to Amelogenin X allele peak height value was 8.45%.However,no Amelogenin Y allele was detected in other 4 plasma DNA samples from pregnant women with female fetus.Conclusion The miniSTR technique is suitable for STR genotyping using fetal DNA in maternal plasma,and it suggests a broad application in noninvasive molecular prenatal diagnosis.

BACKGROUND: ABO is the most important blood group system for blood transfusion. Though widely used in determining ABO blood group for its simplicity and rapidity, serological technology has its inherent limitation, for which ABO genotyping provides a valuable alternative.OBJECTIVE: To study ABO gene polymorphism in Chinese Han population and apply ABO genotyping technique to solve serological problems in clinical practice of blood transfusion.DESIGN: Comparison of ABO genotyping results of random selected samples with those of routine serological phenotyping.SETTING: An institute of transfusion medicine in a municipal blood center.PARTICIPANTS: Totally 260 unrelated healthy Chinese blood donors of Han nationality were randomly selected in Shenzhen Blood Center from March to December in 2002, including 110 male and 150 female subjects aged between 18 and 50 years. A sample with discrepancy in serological ABO phenotype was from our blood center, and the donor' s family was investigated. Six samples suspected to be A2 phenotype by serological test were from four hospitals in Shenzhen including the Second People' s Hospital of Shenzhen.METHODS: The DNA was extracted from the peripheral blood by rapid salt fractionation, and subjected to polymerase chain reaction(PCR) with sequence-specific primers (PCR-SSP) to amplify the ABO gene for ABO genotyping. The alleles of the blood type difficult to determine were amplified with PCR-SSP on the basis of serologic tests including absorption and elution test and agglutination inhibition assay of salivary blood-group substances.MAIN OUTCOME MEASURES: Genotypes and phenotypes of the blood samples from 260 individuals and of the samples with serological ABO discrepancy.RESULTS: In the 260 Chinese Han individuals, in accordance with Hardy-Weinberg equilibrium, the gene frequencies of O1, B, A1O1(A467c), A1O2/1O3(A467T) alleles were 0. 582 7, 0. 184 6, 0. 009 6, and 0. 2231, respectively. Two of the six individuals with difficulty of blood type determination and suspected to have A2 phenotype by serological tests proved to have A2O1O1 genotype, and the rest were all of A1O2/A1O3O1. Three children of a family with difficult identification were para-Bombay types, and their ABO types were A102B, A102B and A102O1, respectively.CONCLUSION: ABO PCR-SSP genotyping is simple, rapid and accurate and can be a valuable complement to serological identification.

T missense mutation in exon 7. No novel point mutation at exons 6 and 7 of ABO gene was detected in the other four samples with B subgroup. Conclusion We define this allele as a novel B allele in Chinese Han individuals. The mutation of this novel allele in which the nucleotide changes from C to T at position 721 in exon 7, resulting in an amino acid change from Arg to Trp, results in the decrease of the enzyme activity. It indicates that the alteration of amino acid at position of 241 is critical to the activity of glycosyltransferases.

Exosomes are vesicle-like structures generated and secreted actively by all kinds of cells.They contain proteins, nucleic acids and also lipids from the original cells, functioning in interactions between cells by shuttling cellular cargoes, and regulation of immune response in the microenvironment.Besides, they play important roles in the oncogenesis and progression of lung neoplasms.Considerable studies have demonstrated great potentials of exosomal proteins and microRNAs as biomarkers for diagnosis, prognosis prediction and treatment of lung cancers, including immunotherapy and targeted delivering of anti-tumor drugs based on exosomes.

Objective To study the molecular genetic background of Bel subtype at ABO blood group.Methods Three samples and fifteen samples were diagnosed as Bel subgroup and normal control samples by serological test,respectively.The extracted DNA was genotyped by sequence specific primer- polymerase chain reaction foilowed by sequencing for Exon6 and exon7 at ABO locus and clones were sequenced.Results A novel Bel variant allele(GenBank EF117687) was identified in a Bel individual.The Bel allele was different from the regular B101 allele by single 952G>A missense mutation in exon7.resulting in an amino acid subsfitution of Val for Met at 318 locus.No mutations were detected in the fifteen control samples and the other two Bel allele samples.Conclusions The mutation position was fimt found to lie on coding region of ABO gene behind nucleotide 930.The mutation of G952A in the al,3 galactosyhransferase gene may be one of the molecular genetic basis of Bel ohenotype.

Objective To investigate serological blood typing of the ABO locus which contradict to general law of inheritance in parentage,and the underlying reasons for severe hemolytic disease of newborn(HDN).Methods To research the family whose newborn is AB phenotypes,mother is O phenotypes and father is AB phenotypes.The familiy were genotyped by parentage tests, serological tests,PCR-SSP and direct DNA sequencing at exons 6 and 7 of ABO gene.At the salne time,HDN was detected by micro column gel Coombs (MGCT), and the primary fingerposts of the routine blood tests. Biochemical tests were dynamically observed.Results The results of parentage tests showed that three-generation pedigree have parent-child relationship. The red blood cell(RBC)of this AB phenotypes of this family members strongly agglutinated(4+)with diverse monoelonal anti-A and anti-B antibodies,and their serum did not contain anti-A and anti-B antibodies in blood anti-typing.PCR-SSP can not detect their A and B gene,but DNA sequencing at exons6 and 7 of ABO gene revealed that it had the B(A)803C→G mutation.Conclusions The genetm basis of this parentage are B(A)803G blood gene which harbored both A and B difunctionality of glyeosyhransferases.This was the first report that severe HDN resulting from a large number of A and B antigens in RBC of B(A)phenotype of a newborn,which has clinical significance on ABO locus.

Objective To study the mutation of FUT1 and FUT2 genes in para-Bombay individual.Methods Direct DNA sequencing of FUT1 and FUT2 gene coding region were analyzed in two individuals with para-Bombay phenotype.Results One individual lost one of the three AG repeats located at nucleotides 547~552 of the FUT1 gene, whereas two of the three T repeats located at nucleotides 880~882 were deleted in the other.Conclusion Two frame-shift mutations of FUT1 gene are responsible for the H antigen deficiency

Objective To explore the effect of hepatitis B virus (HBV) X protein (HBx) on autotaxin (ATX) expression and its significance. Methods The recombinant eukaryotic expression vector of HBx ,pcD-NA3.1(+)-HBx,and the recombinant luciferase reporter gene vector of ATX promoter,pGL3-ATX,were con-structed and used to co-transfect HepG2 cells to examine the effect of HBx on the activity of ATX promoter. The sta-ble cell expressing HBx,HepG2.HBx,was constructed,and Western blot(WB)was used to detect the effect of HBx on ATX expression. Results The luciferase activity of pcDNA3.1(+)-HBx and pGL3-ATX group was 1.47 times as that of the empty vector cDNA3.1(+)and pGL3-ATX group(P<0.000). WB detection showed that the expression of ATX protein was increased in HepG2.HBx cells,and 1.75 times as that of HepG2 cells(P<0.05). Conclusion HBx can activate ATX promoter and up-regulate ATX expression ,thus suggests that HBV infection might enhance ATX/LPA signaling.

OBJECTIVETo study the molecular genetic background of B subtype in Chinese Han population and identify novel allele at the ABO locus.

METHODSTen samples from randomly selected blood donors of normal B phenotype used as control, and six samples from individuals diagnosed as B subgroup by serological tests were genotyped by sequence specific primer polymerase chain reaction and direct DNA sequencing at the exons 6 and 7 of ABO gene. The exons 6 and 7 and the intervening intron 6 of the B allele from each B subgroup sample were analyzed by cloning and haplotype sequencing.

RESULTSA novel B variant allele was identified in two individuals whose blood samples were diagnosed as belonging to Bx subgroup and Bw subgroup respectively, the novel B allele being different from the allele B101 by single 695T>C missense mutation in exon 7. A family with the individual possessed Bx subgroup was studied. Among 22 family members tested, seven family members were found to carry the novel B variant allele. No novel point mutation at the exons 6 and 7 of ABO gene were detected in the ten control samples and the other four samples with B subgroup.

CONCLUSIONThe present authors define this allele as a novel B variant allele. The mutation of this novel allele, in which the nucleotide alters from T to C at position of 695 in exon 7 and hence results in an amino acid change from Leu to Pro, is expected to diminish the enzyme's activity. It indicates that the alteration of amino acid at the position of 232 is critical to the activity of glycosyltransferases.

ABO Blood-Group System ; genetics ; Alleles ; Asian Continental Ancestry Group ; genetics ; China ; DNA Mutational Analysis ; Exons ; Family Health ; Female ; Humans ; Introns ; Male ; Mutation, Missense ; Pedigree ; Polymerase Chain Reaction

OBJECTIVE: To develop a genotyping method for the Junior blood type and report on a rare blood type with Jr(a-). METHODS: Healthy O-type RhD+ volunteer donors of the Shenzhen Blood Center from January to May 2021 (n = 1 568) and a pedigree with difficult cross-matching (n = 3) were selected as the study subjects. Serological methods were used for proband's blood type identification, unexpected antibody identification, and antibody titer determination. Polymerase chain reaction-sequence specific primer (PCR-SSP) method was used for typing the proband's RhD gene. ABCG2 gene coding region sequencing and a PCR-SSP genotyping method were established for determining the genotypes of the proband and his family members and screening of Jra antigen-negative rare blood type among the 1 568 blood donors. RESULTS: The proband's ABO and RhD blood types were respectively determined as B and partial D (RHDDVI.3/RHD01N.01), Junior blood type Jra antigen was negative, and plasma had contained anti-D and anti-Jra. Sequencing of the ABCG2 gene revealed that the proband's genotype was ABGG201N.01/ABGG201N.01 [homozygous c.376C>T (p.Gln126X) variants], which is the most common Jr(a-) blood type allele in the Asian population. Screening of the voluntary blood donors has detected no Jr(a-) rare blood type. Statistical analysis of the heterozygotes suggested that the allelic frequency for ABCG2*01N.01 (c.376T) was 0.45%, and the frequency of Jr(a-) rare blood type with this molecular background was about 0.2‰. CONCLUSION A very rare case of partial DVI.3 type and Jr(a-) rare blood type has been identified. And a method for identifying the Junior blood type through sequencing the coding regions of the ABCG2 gene and PCR-SSP has been established.
Humans ; Blood Group Antigens/genetics* ; Genotype ; Genotyping Techniques ; Heterozygote ; Alleles ; Blood Donors ; Rh-Hr Blood-Group System/genetics*