Evaluation of High Resolution Melting Technique for Detection of JAK2-V617F Mutation in Formalin-Fixed Paraffin-Embedded Specimen from Myeloproliferative Neoplasm Cases

@#Introduction: Myeloproliferative neoplasm (MPN) is a group of myeloid disorders which leads to erythrocytosis, thrombocytosis and leucocytosis. MPN with BCR-ABL positive is chronic myeloid leukaemia (CML) while BCR-ABL negative MPN includes polycythaemia Vera (PV), essential thrombocytemia (ET) and primary myelofibrosis (PMF). One of the major criteria for diagnosis of BCR-ABL negative MPN is the presence of JAK2-V617F mutation which is positive in 95% of PV and around 60% of ET and MF. Beside peripheral blood specimen, formalin-fixed paraffin-embedded (FFPE) marrow specimen can be used for detection of this mutation. Unfortunately, FFPE produces low quality DNA that put a challenge for successful amplification of DNA. We aimed to evaluate the utility of High Resolution Melting (HRM) analysis for detection of JAK2-V617F mutation in FFPE specimen from MPN cases. Materials and Methods: This study is a descriptive crosssectional study. Forty FFPE marrow specimens were retrieved from the years 2014-2016. Bio-Rad Precision Melt Analysis software was used for analysis of HRM data. Allele-specific PCR was done for validation of results. Positive samples were subjected to Sanger sequencing. Results: JAK2-V617F mutation was positive in 13 out of 40 MPN cases. Level of agreement between HRM and AS-PCR was 97.5%. Conclusion: HRM is a rapid and powerful diagnostic assay which is suitable for detection of JAK2-V617F mutation in FFPE marrow specimen.

Detection of quinolone-resistance mutations in Salmonella spp. strains of epidemic and poultry origin

Mutations into codons Aspartate-87 (62 percent) and Serine-83 (38 percent) in QRDR of gyrA were identified in 105 Salmonella strains resistant to nalidixic acid (94 epidemic and 11 of poultry origin). The results show a high incidence of mutations associated to quinolone resistance but suggest association with others mechanisms of resistance.

A Simplified ABO Genotyping by Allele-Specific Polymerase Chain Reaction / 대한진단검사의학회지

BACKGROUND: Genotyping of ABO gene could be more informative and valuable than serological typing in some situations such as the resolution for ABO discrepancy between the cell typing and serum typing and determination of A and B subgroups. We developed a simple allele-specific polymerase chain reaction (AS-PCR) method without the use of any restriction enzymes to detect the A, B, O, and cis-AB alleles for Koreans. METHODS: An AS-PCR was designed with amplification refractory mutation system (ARMS) at nt (nucleotide) 261 (exon 6) and at nt 526, 803 (exon 7) of ABO gene to detect specific nucleotide sequence differences between the ABO alleles. We tested for ABO genotyping 60 DNA samples previously tested by PCR-RFLP and stored at -70degreeC. These samples had been obtained from blood donors recruited at the Gwangju-Chonnam Red Cross Blood Center between July 2002 and February 2003. RESULTS: With our new PCR method, the genotypes of the 60 samples were found to be A/O (n=10), A/A (n=5), B/O (n=10), B/B (n=5), O/O (n=10), cis-AB/A (n=5), cis-AB/B (n=5), and cis-AB/ O (n=10), which were the s ame results obtained previously with PCR-RFLP. CONCLUSIONS: Our AS-PCR is a simple and accurate method for the detection of A, B, O, and cis-AB alleles for Koreans.