Abstract: Objective　To investigate the HP (Helicobacter pylori) infection and ITPs (Immune thrombocytopenia) susceptibility genes and protective genes by detecting HLA-DRB1*03、*04、*07、*11、*14 alleles in ITP patients，HP patients，the patients with HP infection and ITP，and healthy children. Methods　Collected the whole blood of ITP patients，HP patients，the patients with HP infection and ITP，and healthy children treated in BCH from May 2014 to January 2015. Extracted DNA from samples and tested the HLA-DRB1*03、*04、*07、*11、*14 allele frequencies by PCR-SSP. Compared the gene frequency among different groups. Results　There are 136 Han nationality children in this study. The distribution frequency of HLA-DRB1*04 was 21.32%，HLA-DRB1*07 was 19.12%，HLA-DRB1*14 was 15.44%，HLA-DRB1*11 was 11.76%，HLA-DRB1*03 was 8.82%. There was no statistically significant difference between genders. Compared to the above HLA alleles frequency in a different group，the frequency of HLA-DRB1*07 in ITP children was 30.5%，in healthy controls was 9.7%(OR=4.1，χ2=4.393，P=0.036). The difference was statistically significant. The frequency of HLA-DRB1*14 in patients with HP infection and ITP was significantly higher than in the HP infection group (OR=4.8，χ2=5.435，P=0.02). Compared the same group but with different gender，the HLA-DRB1*04 alleles frequency of the girls with HP infection(40%) was higher than the boys with HP infection(4.8%). According to statistical analysis，there was a significant difference between the two groups. Conclusion　HLA-DRB1*07 allele may be the susceptibility gene of ITP. HP infected children with the HLA-DRB1*14 allele may have a higher risk to develop ITP. HLA-DRB1*04 allele may be the susceptibility gene of girls infected with HP. 

Key words: Helicobacter Pylori, Immune thrombocytopenia, HLA-DRB1, child

摘要： 目的　通过对幽门螺杆菌（Helicobacter pylori，HP）感染、免疫性血小板减少症（immune thrombocytopenia，ITP）、ITP合并HP感染患儿及健康儿童进行HLA-DRB1*03、*04、*07、*11、*14等位基因检测，探究HP感染及ITP的易感性基因及保护性基因。方法　收集北京儿童医院2014年5月至2015年1月HP感染患儿、ITP患儿、HP感染合并患儿及健康儿童的全血标本，提取全血DNA，应用PCR-SSP方法检测四组患儿HLA-DRB1*03、*04、*07、*11、*14等位基因表达频率，对比不同性别、不同组别之间基因表达频率的差异性。结果　选取的136例汉族儿童中，检测的5种HLA-DRB1等位基因分布频率分别为HLA-DRB1*04（21.32%）、HLA-DRB1*07（19.12%）、HLA-DRB1*14（15.44%）、HLA-DRB1*11（11.76%）、HLA-DRB1*03（8.82%）。分别比较以上5种等位基因在男女性别间的频率表达，差异无统计学意义；在比较HP组与健康对照组、ITP组与健康对照组、HP+ITP组与HP组、HP+ITP组与ITP组以上5种等位基因表达频率的差异性后发现，HLA-DRB1*07等位基因在ITP患儿和健康儿童的表达频率分别为：30.5%、9.7%（OR值=4.1，χ2=4.393，P=0.036），差异具有统计学意义；HP感染合并ITP患儿携带HLA-DRB1*14等位基因的频率明显高于单一HP感染患儿（OR值=4.8，χ2=5.435，P=0.02）；在比较相同组别、不同性别间5种等位基因的分布频率后发现，HLA-DRB1*04等位基因在HP感染女童中的表达频率（40%）明显高于HP感染男童（4.8%），经统计学分析，此等位基因在两组间的表达频率差异具有显著性（P=0.013）。结论　HLA-DRB1*07基因可能是ITP的易感性基因；HLA-DRB1*14（+）的HP感染患儿继发ITP的可能性更大，HLA-DRB1*04基因可能是女童感染HP的易感性基因。

关键词: 幽门螺杆菌感染, 免疫性血小板减少症, HLA-DRB1, 儿童