Amino Acid Substitution ; Antineoplastic Agents/pharmacology* ; Cell Line, Tumor ; Drug Resistance, Neoplasm/genetics* ; Gastrointestinal Neoplasms/pathology* ; Humans ; MAP Kinase Signaling System/genetics* ; Mutation, Missense ; Receptor, ErbB-3/metabolism* ; Receptor, Fibroblast Growth Factor, Type 1/metabolism*

OBJECTIVE: To explore the molecular basis for a blood donor with an ABO subtype. METHODS: The proband and his family members were subjected to serological analysis. Their genotypes were determined by real-time PCR and sequencing of the coding regions of ABO gene. RESULTS: The proband was determined as an ABw subtype. By sequencing analysis, the proband was typed as A102/BW03. Compared with ABO*B.01, the proband was found to harbor a 721C>T variant (ABO*BW.03 allele) in exon 7 of the ABO gene, which caused substitution of Arginine at position 241 by Tryptophan resulting in a ABW phenotype. The blood type of the proband's sister was similar to that of the proband. The maternal serological pattern was B type, and the result of sequencing suggested that the genotype fit with B101/Bw03. CONCLUSION The 721C>T in the exon 7 of the ABO glycosyltransferase gene probably underlies the Bw03 phenotype. The ABO*Bw.03 variant of the proband and his sister were inherited from their mother.
ABO Blood-Group System ; genetics ; Amino Acid Substitution ; Female ; Genotype ; Humans ; Male ; Pedigree ; Whole Exome Sequencing

Isolates of 24 enterococci, 5 Enterococcus casseliflavus and 19 Enterococcus gallinarum, possessing vanC genes and showing low-level resistance to vancomycin were obtained from mice from commercial mouse breeding companies. Since some of these isolates showed resistance to other antibiotics, the purpose of this study was to clarify the resistant profiles of these isolates. One E. casseliflavus isolate showed resistance to erythromycin with a minimal inhibitory concentration (MIC) of 8 μg/mL and also showed apparent resistance to fluoroquinolones with an MIC of 32 μg/mL for ciprofloxacin. The MICs of 2 other fluoroquinolone-resistant E. casseliflavus and E. gallinarum isolates were 3 and 6 μg/mL, respectively. These 3 resistant isolates showed an absence of macrolide- and fluoroquinolone-resistant genes, including amino acid substitutions in the quinolone resistance determining regions of DNA gyrase and topoisomerase IV. Resistance to tetracycline was detected in 2 E. gallinarum isolates that were highly resistant, exhibiting MICs of 48 and 64 μg/mL and possessing tet(O) genes. The results indicate that antibiotic-resistant enterococci are being maintained in some laboratory mouse strains that have never been treated with an antibiotic.
Amino Acid Substitution ; Animals ; Anti-Bacterial Agents ; Breeding ; Ciprofloxacin ; DNA Gyrase ; DNA Topoisomerase IV ; Drug Resistance, Microbial ; Enterococcus ; Erythromycin ; Fluoroquinolones ; Mice ; Tetracycline ; Vancomycin

No abstract available.
Amino Acid Substitution ; Korea ; Penicillin-Binding Proteins ; Penicillins ; Streptococcus

BACKGROUND: Enterococcus faecalis strains with low-level resistance to linezolid (an oxazolidinone antibiotic) have become common. No large-scale study has examined the underlying mechanisms in linezolid-resistant E. faecalis (LRE) strains. We investigated these mechanisms and molecular characteristics in Chongqing, China. METHODS: A total of 1,120 non-duplicated E. faecalis strains collected from August 2014 to June 2017 underwent drug susceptibility testing. LRE strains were screened for optrA, cfr, and mutations in the 23S rRNA and ribosomal proteins L3 and L4 by PCR amplification and sequencing. Multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were used for epidemiological analysis. RESULTS: All 43 low-level LRE strains (minimum inhibitory concentration: 8–16 mg/L) harbored optrA; cfr and 23S rRNA mutations were not detected. Novel mutations in the ribosomal proteins L3 and L4—one deletion (Q103del) and four substitutions (S113L, T35A, I98V, and N79D)—were identified. Novel amino acid substitutions at positions E60K, G197D, and T285P of the OptrA protein were observed. MLST revealed 20 types of LRE strains; the most common type was ST16 (32.6%). PFGE showed 14 strains of ST16 with unique banding patterns. Eight novel sequence types (ST823 to ST830) and one allele (gki95) were identified for the first time in China. CONCLUSIONS: optrA plays an important role in linezolid resistance and may serve as a marker for resistance screening. Since the L3 and L4 mutations did not simultaneously occur in the same strain, they play a negligible role in linezolid resistance. Epidemiological investigation suggested that the LRE cases were sporadic.
Alleles ; Amino Acid Substitution ; China* ; Electrophoresis, Gel, Pulsed-Field ; Enterococcus faecalis* ; Enterococcus* ; Epidemiology ; Linezolid ; Mass Screening ; Molecular Epidemiology* ; Polymerase Chain Reaction ; Ribosomal Proteins

OBJECTIVE: To explore the serological and molecular characteristics of a female with the B(A) phenotype and safety issues related to her blood transfusion. METHODS: The B(A) phenotype of the proband was confirmed by serological testing. Her genotype was determined by using polymerase chain reaction-sequence specific primer (PCR-SSP) and direct sequencing of exons 6 and 7 of the ABO locus. Clinical condition of her blood transfusion was also reviewed. RESULTS: Both A and B antigens were detected on the red blood cells derived from the proband, while anti-A antibody was detected in her serum. The result of PCR-SSP suggested that she has a B/O02 phenotype. DNA sequencing revealed presence of 297A>G, 526C>G, 657C>T, 700C>G, 703G>A, 796C>A, 803G>C and 930G>A mutations. The genotype of the proband was deduced as B(A) 02/O02. Compared with the B101 allele, the B(A)02 allele has a nucleotide change (C>G) at position 700, which resulted in substitution of an amino acid (P234A). The result of cross match testing between the proband and two donors with an AB phenotype was consistent. No adverse reaction was observed after the transfusion. CONCLUSION 700G>C of B allele can result in the B(A) phenotype, which is similar to AB. Blood donors for individuals with the B(A) phenotype should include those with an AB phenotype.
ABO Blood-Group System ; genetics ; Alleles ; Amino Acid Substitution ; Blood Grouping and Crossmatching ; Blood Transfusion ; Exons ; Female ; Genotype ; Humans ; Phenotype ; Polymorphism, Single Nucleotide

OBJECTIVE: To explore the molecular basis for an individual with Ax28 phenotype of the ABO subtype. METHODS: The ABO group antigens on red blood cells of the proband were identified by monoclonal antibodies. The ABO antibody in serum was detected by standard A, B, O cells. Exons 1 to 7 of the ABO gene were respectively amplified by PCR and directly sequenced. Amplicons for exons 5 to 7 were also sequenced after cloning. RESULTS: Weakened A antigen was detected on red blood cells from the proband. Both anti-A and anti-B antibodies were detected in the serum. Heterozygous 261G/del was detected in exon 6, while heterozygous 467C/T and 830T/C were detected in exon 7 by direct DNA sequencing. After cloning and sequencing, two alleles (O01 and Ax28) were obtained. Compared with A102, the sequence of Ax28 contained one nucleotide changes (T to C) at position 830, which resulted in amino acid change (Val to Ala) at position 277. CONCLUSION The novel mutation c.830T>C of the galactosaminyltransferase gene may give rise to the Ax28 phenotype.
ABO Blood-Group System ; genetics ; Alleles ; Amino Acid Substitution ; Exons ; Galactosyltransferases ; genetics ; Genotype ; Humans ; Phenotype ; Polymorphism, Single Nucleotide ; Sequence Deletion

PURPOSE: X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by mutations in the Bruton's tyrosine kinase (Btk) gene. The aim of this study was to investigate the clinical manifestations, molecular features, and treatment status of XLA in Korean patients at Seoul National University Children's Hospital. METHODS: Fourteen Korean boys with XLA showing serum agammaglobulinemia, non-detectable to less than 2% of peripheral B-cells, and mutation of the Btk gene were enrolled. We observed the clinical features, laboratory findings, status of treatment, and complications in these XLA patients. RESULTS: All XLA patients had a history of recurrent bacterial infections before diagnosis, and 20% of them had a neutropenia. Of the XLA patients 35.7% had a family history of XLA and 75% of their mothers were carriers. Btk gene analysis showed variable gene mutations in Xq22 including 9 amino acid substitutions, 3 frameshifts, 1 premature stop codon, and 1 splice defect. After intravenous immunoglobulin replacement therapy, infection episodes decreased, but complications such as bronchiectasis and chronic sinusitis remained. CONCLUSIONS: In patients less than 4 years of age with recurrent infection, analysis of serum gamma globulin levels and the Btk gene are recommended for the early diagnosis of XLA and for the appropriate prevention of recurrent infection.
Agammaglobulinemia* ; Amino Acid Substitution ; B-Lymphocytes ; Bacterial Infections ; Bronchiectasis ; Codon, Nonsense ; Diagnosis ; Early Diagnosis ; gamma-Globulins ; Humans ; Immunoglobulins ; Immunoglobulins, Intravenous ; Mothers ; Neutropenia ; Protein-Tyrosine Kinases ; Seoul ; Sinusitis

PURPOSE: X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by mutations in the Bruton's tyrosine kinase (Btk) gene. The aim of this study was to investigate the clinical manifestations, molecular features, and treatment status of XLA in Korean patients at Seoul National University Children's Hospital. METHODS: Fourteen Korean boys with XLA showing serum agammaglobulinemia, non-detectable to less than 2% of peripheral B-cells, and mutation of the Btk gene were enrolled. We observed the clinical features, laboratory findings, status of treatment, and complications in these XLA patients. RESULTS: All XLA patients had a history of recurrent bacterial infections before diagnosis, and 20% of them had a neutropenia. Of the XLA patients 35.7% had a family history of XLA and 75% of their mothers were carriers. Btk gene analysis showed variable gene mutations in Xq22 including 9 amino acid substitutions, 3 frameshifts, 1 premature stop codon, and 1 splice defect. After intravenous immunoglobulin replacement therapy, infection episodes decreased, but complications such as bronchiectasis and chronic sinusitis remained. CONCLUSIONS: In patients less than 4 years of age with recurrent infection, analysis of serum gamma globulin levels and the Btk gene are recommended for the early diagnosis of XLA and for the appropriate prevention of recurrent infection.
Agammaglobulinemia* ; Amino Acid Substitution ; B-Lymphocytes ; Bacterial Infections ; Bronchiectasis ; Codon, Nonsense ; Diagnosis ; Early Diagnosis ; gamma-Globulins ; Humans ; Immunoglobulins ; Immunoglobulins, Intravenous ; Mothers ; Neutropenia ; Protein-Tyrosine Kinases ; Seoul ; Sinusitis

The timing of puberty onset varies greatly among individuals, and much of this variation is modulated by genetic factors. This study aimed to identify the kisspeptin receptor (KISS1R) gene variations and to investigate the associations between these variations and central precocious puberty (CPP). Korean girls with CPP (n = 194) and their healthy controls (n = 99) were included in this study. The entire coding region and the exon-intron boundaries (exon 1 through 5) of the KISS1R gene were directly sequenced. Seven polymorphisms were identified in the KISS1R gene. A missense change c.1091T>A, and an intron variant c.738+64G>T showed significantly higher allele frequencies in CPP patients than in controls (c.1091T>A: 30.7% vs. 22.2%, P = 0.031; c.738+64G>T: 45.6% vs. 35.9%, P = 0.023). The missense variant (c.1091T>A) was a nonsynonymous polymorphism that induces amino acid substitution of p.Leu364His. The haplotype CAGTGTC was detected more frequently in the CPP group (P = 0.042). The sequence variants of the KISS1R gene can be inducible factors in the development of CPP. The association between sequence variants and CPP should be validated by further evidence obtained from larger samples of children with CPP.
Adolescent ; Amino Acid Substitution ; Child ; Clinical Coding ; Female* ; Gene Frequency ; Genetic Variation* ; Haplotypes ; Humans ; Introns ; Puberty ; Puberty, Precocious*