실시간 반정량 PCR, JAK2 MutaScreenTM kit를 이용한 JAK2 V617F 유전자 변이 선별검사의 유용성 = Usefulness of Real-time Semi-quantitative PCR, JAK2 MutaScreenTM Kit for JAK2 V617F Screening

다국어 초록 (Multilingual Abstract)

Background : Real-time PCR for quantification of JAK2 V617F has recently been introduced and used to evaluate the importance of mutant allele burden in both diagnosis and disease progression in myeloproliferative diseases (MPDs). We evaluated the usefulness of JAK2 MutaScreenTM kit that
uses a real-time semiquantitative PCR method and has been designed to screen JAK2 V617F mutant allele burden.
Methods : Forty MPD patients were included in this study. We screened JAK2 V617F and determined the mutant allele burden using JAK2 MutaScreenTM kit. The mutant allele burden was estimated by six-scaled standards of JAK2 V617F mutant allele (2%, 5%, 12.5%, 31%, 50%, and 78%). For evaluation of test performance, an allele-specific PCR (AS-PCR) was carried out in all samples by using Seeplex JAK2 Genotyping kit. We assessed the clinical differences in distinct disease entities of MPDs according to JAK2 V617F mutant allele burden.
Results : JAK2 V617F mutation was detected in 30 cases, including 10 of 11 cases (91%) of polycythemia vera (PV), 13 of 20 cases (65%) of essential thrombocythemia (ET), and 2 of 3 cases (67%) of chronic idiopathic myelofibrosis (CIMF). The concordance rate between the two tests was 95%
(38/40). JAK2 V617F mutant allele burden was greater than 50% in 17 cases, and 10 of them (59%) were PV. In contrast, mutant allele burden was less than 50% in 13 cases and 11 of them (85%) were ET.
Conclusions : JAK2 MutaScreenTM kit that utilizes a real-time semi-quantitative PCR method is a useful tool for diagnosing MPDs precisely. It can be used to assess the grade of mutant allele burden as well as to screen JAK2 V617F simultaneously.

국문 초록 (Abstract)

배경 : 최근 JAK2 V617F 유전자 변이에 실시간 정량 PCR법
을 이용한 검사법이 소개되어 MPDs의 진단과 질환의 진행에
있어 유전자 변이량 측정의 중요성 평가에 사용되고 있다. 저자
들은 JAK2 V617F 유전자 변이 선별을 위해 새로이 고안된 실
시간 반정량 PCR법인 JAK2 MutaScreenTM kit의 유용성을 평
가하였다.
방법 : 40예의 MPDs 환자를 대상으로 JAK2 MutaScreenTM
kit를 이용하여 JAK2 V617F 선별 및 유전자 변이량을 측정하
였다. JAK2 V617F 유전자 변이량 측정에는 6단계의 표준물질
을 사용하였다(2%, 5%, 12.5%, 25%, 31%, 50%, 78%). 검사 수
행능의 평가를 위하여 동일한 모든 검체에 대하여 Seeplex JAK2
Genotyping kit을 이용한 AS-PCR법으로 시행한 검사 결과와
비교하였다. 또한 각 MPDs의 질환군과 유전자 변이량에 따른
임상적 특성의 차이를 분석하였다.
결과 : 30예에서 JAK2 V617F 유전자 변이가 검출되었으며 각
질환별 양성률은 PV 91% (10/11), ET 65% (13/20), CMIF 67%
(2/3)였다. 두 검사방법 간의 일치율은 95%였다(38/40). JAK2
V617F 유전자 변이량이 50% 이상인 17예 중 10예가 PV였으며,
JAK2 유전자 변이량이 50% 이하인 13예 중에서는 11예가 ET였
다(85%).
결론 : 실시간 반정량 PCR법을 이용한 검사법인 JAK2 V617F
MutaScreenTM kit는 유전자 변이 검출 및 유전자 변이량의 동
시 측정이 가능하므로 보다 정밀한 MPDs의 진단에 유용한 검
사방법으로 생각된다.

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