<p><b>OBJECTIVE</b>To analyze the
mutation rate and clinical characteristics of CALR, MPL W515K and JAK2 V617F
genes in
patients with
primary thrombocythemia (PT).</p><p><b>
METHODS</b>Fifty-six
patients with PT were selected as the
research objects in our
hospital. The CALR and MPL W515K
gene mutations were determined by genomic
DNA-
PCR direct sequencing of the
PCR products, and the JAK2 V617F
gene mutation was detected by
allele specific
PCR method.</p><p><b>RESULTS</b>Among the 56
patients with PT there were 14 cases of CALR
gene mutation with the
incidence rate of 25%, including 6 cases of type I, 5 cases of type II and 3 cases of type III. The
sex, age,
platelet(Plt) count,
white blood cell (WBC) count and
hemoglobin (Hb) level in the type I case of CALR
gene mutation all were not significantly different from that in type II and III(all P>0.05); the WBC level in type III group significantly increased in comparison of type II group (P<0.05), while the
sex, age, Hb and Plt levels showed no significant difference between the type III and type II groups (P>0.05). There were 3 cases of MPL W515K
gene mutation with the
incidence rate of 5.36%; 21 cases of JAK2 V617F
gene mutation with the
incidence rate of 37.50%. There were 13 cases of CALR
gene mutation in negative
patients with MPL W515K and JAK2 V617F (18 cases) with 72.22%
incidence rate (13/18), and there was no cases of 1 or 2
gene mutations coexisted. The levels of Hb and WBC in peripheral
blood of
patients with CALR
mutation were significantly lower than those of JAK2 V617F
mutation (both P<0.05). In 56 cases, there were 3 cases of
abnormal karyotype, with the
incidence rate of 5.36%. The
mutation rate of CALR
gene in
abnormal karyotypes (66.67%) was significantly higher than that of normal
karyotypes (20.75%) (P<0.01).</p><p><b>CONCLUSION</b>The
incidence of JAK2 V617F
gene mutation increases in the
patients with
primary thrombocythemia; CALR
mutation rate is higher in the
patients with negative MPL W515K and JAK2 V617F
gene mutation, which may closely correlate with
abnormal karyotype; the levels of peripheral Hb and WBC in PT the
patients with CALR
gene mutation are significantly lower than those in
patients with JAK2 V617F
mutation.</p>