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[Background and Purpose] 2005 several international research groups almost simultaneously reported in myeloproliferative neoplasms (MPN) JAK2V617F mutation was found, but in myelodysplastic syndrome (MDS) in a lower incidence. Foreign reports JAK2V617F mutation in MDS patients the incidence rate of 5%, but few reports about its clinical significance, given the current domestic research yet to see on JAK2V617F mutation reported in the literature, we build a viable allele-specific PCR ( AS-PCR) detection technology, 160 cases of MDS bone marrow or peripheral blood specimens were JAK2V617F mutation analysis and preliminary study with MDS classification, clinical characteristics and relationship with MDS disease progression. 2009 abroad have reported that in MDS patients found far the most frequently mutated gene abnormality-TET2 gene mutation rate of 22.9% has been reported, is not yet see related story, we passed AS-PCR amplification products after sequencing, were detected 24 cases of MDS patients TET2 gene in exon 11, and TET2 gene mutation and MDS correlation between clinical features and prognostic significance of a preliminary analysis. [Method] The first part: through the establishment of allele-specific PCR method to study 160 cases of MDS patients JAK2V617F mutation occurrence. 160 cases of MDS patients in our hospital from May 2006 to May 2009 in our hospital outpatient and inpatient. In accordance with the 2001 World Health Organization (WHO) classification diagnostic criteria, RA type 69 cases, RAS 8 cases, RCMD 8 cases, RAEB-1 type 22 cases, RAEB-2 in 28 cases, MDS-U type 20 cases, 5q-syndrome in four cases. 20 normal controls with normal physical examination in our hospital. The main methods are: (a) collecting bone marrow or peripheral blood 2ml, Ficoll-paque mononuclear cells were isolated by using genomic DNA extraction kit for DNA extraction; (2) using allele specific PCR (AS -PCR) amplification of the JAK2 gene, PCR products were subjected to agarose gel electrophoresis, mutation positive patients screened PCR products were confirmed by sequencing. (3) by means of statistical analysis JAK2 mutation and some correlation between clinical parameters. Part II: By AS-PCR amplification products after sequencing methods, detection of 24 cases of MDS patients TET2 gene exon 11 mutations were observed. 24 cases of MDS patients in our hospital from May 2006 to May 2009 in our hospital outpatient and inpatient. In accordance with the 2001 World Health Organization (WHO) classification diagnostic criteria, RA 7 cases, RAS 5 cases, RAEB-1 in 5 cases, RAEB-2 in 5 cases, MDS-U type 2 cases. 10 normal controls with normal physical examination in our hospital. The main methods are: (1) the use of genomic DNA extraction kit for DNA extraction portion with the first portion; (2) allele-specific PCR (AS-PCR) amplification of TET2 gene, PCR products were agarose gel electrophoresis, all occurrences of the target band PCR products were sequenced, compared to the normal gene mutation was found abnormal TET2. [Results] 1.160 cases of MDS patients JAK2V617F mutation in 8 cases, the mutations in Chinese patients with MDS incidence of 5%. None of the 20 normal controls mutation positive. 2 After 1-36 months of follow-up found that the dynamic, 160 cases occurred in patients with MDS, 12 patients with acute leukemia transformation (17.1%), with a median conversion time of 3 (1 ~ 13) months, including M2 6 cases (50% ), M4 2 例 (16.7%), M5 2 例 (16.7%), M6 2 cases (16.7%). JAK2 gene mutations in patients with conversion was 37.5% (3/8) 5.9% higher than the wild-type (9/152), the difference was statistically significant (P = 0.004). 3.24 cases of MDS patients detected in two cases TET2 mutation that MDS patients in China incidence of 8.3%. 03 specimens in the third exon appear on the first 273 amino acid deletion mutant C, the specimen on the 18th in the 7th exon appear on the first 1298 amino acids GC mutation. None of the 10 normal controls mutation positive. 4.2 cases TET2 gene mutations in wild-type and 22 cases in the general clinical characteristics between the difference was not statistically significant, but one case of MDS progression to M4 mutant TET2 after genetic testing still found the same mutation, because the specimens were fewer cases , still can not analyze this mutation and the relationship between MDS prognosis. [Conclusion] 1. Chinese MDS patients JAK2V617F mutation rate was 5%, consistent with the conclusions of relevant reports abroad. 2.8 cases of mutations in patients with RAEB-2 type 3 cases (37.5%), RAEB-1 type 2 cases (25%), MDS-U type 2 cases (25%), RCMD type 1 cases (12.5%). JAK2V617F mutation between MDS subtypes were no significant differences in clinical characteristics generally no significant difference, but the mutant AL conversion rate in the wild type, JAK2V617F mutation and secondary MDS AL has some relevance. 3 Chinese MDS patients TET2 mutation rate was 8.3%, lower than the foreign-related reports, the conclusion remains to expand the sample size further verification. 4. MDS patients with TET2 mutations are single changes, including one case prompted TET2 mutations in MDS disease progression mutation is relatively stable, may be associated with secondary MDS AL no significant correlation. However, the prognosis of MDS correlation samples to be expanded further study.
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