Nonalcoholic steatohepatitis in Asian Indians is neither associated with iron overload nor with HFE gene mutations

AIM: The pathogenesis of occurrence of liver inflammation and fibrosis in patients with nonalcoholic steatohepatitis (NASH) is not completely understood. Other than insulin resistance, iron abnormalities have been thought to be one of the triggering factors. Therefore, our aim was to study the role of iron abnormalities and HFE gene mutations in patients with NASH. METHODS: Thirty-one patients of NASH diagnosed on the basis of clinical examination biochemistry, ultrasonography and liver biopsy (n = 14) were included in the study. Serum iron parameters (n = 23) (iron, ferritin, total iron-binding capacity and transferrin saturation), Perls' iron staining on liver biopsies (n = 14) and HFE gene mutations (C282Y and H63D) (n = 16) were studied in these patients. The association between iron staining, necroinflammatory activity and fibrosis stage on liver biopsies was also determined. RESULTS: Elevated serum iron, ferritin and transferrin saturation above 55% were observed in 4.3% of patients. On histology, 71% of the patients had negative iron staining, 21.4% had 1+ staining, 7.2% had 2+ staining and none had 3+ or 4+ staining. There was no association between the degree of iron staining and necroinflammatory activity (P=0.55) and fibrosis stage (P= 0.09) on histology. None of the patients had C282Y HFE gene mutation and four patients (25%) were found to be heterozygotes for H63D gene mutation. CONCLUSION: Our study does not favor iron overload and HFE gene mutations as major factors in the pathogenesis of NASH in Asian Indians.

Frequency of primary iron overload and HFE gene mutations (C282Y,H63D and S65C) in chronic liver disease patients in north India

AIM:To identify the frequency of iron overload and study the three mutations in the HFE gene (C282Y,H63D,and S65C) in patients with chronic liver disorders (CLD) and controls. METHODS:To identify patients with iron overload (transferrin saturation > 45% in females and > 50% in males and serum ferritin > 1000 ng/mL) we evaluated 236 patients with CLD,including 59 with non-alcoholic steatohepatitis (NASH),22 with alcoholic liver disease (ALD),19 of cirrhosis due to viruses (HBV,HCV),and 136 with cryptogenic cirrhosis. Mutations of the HFE gene were analyzed by PCR-RE. hundred controls were screened for iron status and the mutations. RESULTS:Seventeen patients with CLD showed evidence of iron overload. Fifteen cases of iron overload had cryptogenic cirrhosis and two had ALD. None of the controls showed iron overload. We did not find any individual with 282Y or 65C either in the cases or in the controls. The prevalence of H63D heterozygosity was 12% in normal individuals,14.8% in 236 patients (16.9% in NASH,13.6% in ALD,26.3% in viral and 12.5% in cryptogenic cirrhosis) and the overall prevalence was 13.98%. Only two of the 17 patients with primary iron overload were heterozygous for H63D. One patient with NASH and one normal individual who were homozygous for H63D showed no iron overload.CONCLUSION:Primary iron overload in Indians is nonHFE type,which is different from that in Europeans and further molecular studies are required to determine the defect in various iron regulatory genes.

Nonalcoholic fatty liver disease and HFE gene mutations:A Polish study

AIM:To describe a Polish population with nonalcoholic fatty liver disease(NAFLD)with regard to HFE gene mutations,as well as analyzing demographic and clinical data.METHODS:Sixty-two consecutive patients with biopsy-proven NAFLD were included in the study.Demographic,clinical,and laboratory data were summarized in a database.C282Y and H63D mutations of the HFE gene were analyzed using polymerase chain reactionrestriction fragment lenght polymorphism.RESULTS:The analyzed cohort consisted of 62 homo-geneic Caucasian participants,66.1%men and 33.9% women,with a median age of 48 years.The median body mass index was 29.05 kg/m 2 .Hypercholesterolemia was observed in 74.2%of patients and hypertriglyceridemia in 32.2%;16.1%had type 2 diabetes mellitus(DMt2).On liver biopsy,22.6%of NAFLD patients were found to have severe fibrosis.There were no differences between frequencies of HFE gene mutations in subgroups of NAFLD patients with less and more severe liver fibrosis.Obesity,older age,female gender and DMt2 were associated with more advanced fibrosis in this Polish cohort,as well as higher glucose level,serum iron and transaminase aspartate aminotransferase/alanine aminotransferase ratio.CONCLUSION:HFE mutations conferred no additional hepatic fibrosis risk in NAFLD,but higher serum iron was a risk factor for severe liver damage in NAFLD,regardless of HFE mutations.

HFE gene in primary and secondary hepatic iron overload

Distinct from hereditary haemochromatosis, hepatic iron overload is a common finding in several chronic liver diseases. Many studies have investigated the prevalence, distribution and possible contributory role of excess hepatic iron in non-haemochromatotic chronic liver diseases. Indeed, some authors have proposed iron removal in liver diseases other than hereditary haemochromatosis. However, the pathogenesis of secondary iron overload remains unclear. The High Fe （HFE） gene has been implicated, but the reported data are controversial. In this article, we summarise current concepts regarding the cellular role of the HFE protein in iron homeostasis. We review the current status of the literature regarding the prevalence, hepatic distribution and possible therapeutic implications of iron overload in chronic hepatitis C, hepatitis B, alcoholic and non- alcoholic fatty liver diseases and porphyria cutanea tarda. We discuss the evidence regarding the role of HFE gene mutations in these liver diseases. Finally, we summarize the common and specific features of iron overload in liver diseases other than haemochromatosis.

Comprehensive analysis of HFE gene in hereditary hemochromatosis and in diseases associated with acquired iron overload

BACKGROUND Patients with hepatitis C virus(HCV) and hepatocellular carcinoma(HCC) may or not develop iron overload(IO),which is associated with worst prognosis,because can cause serious damage to organs.HFE gene controls the iron uptake from gut,particularly in patients with hereditary hemochromatosis(HH).AIM To identify associations between HFE coding region in patients exhibiting hereditary hemochromatosis and in diseases associated with acquired IO.METHODS We sequenced exons 2 to 5 and boundary introns of HFE gene,evaluating all polymorphic sites in patients presenting hereditary(hemochromatosis) or acquired iron overload HCV and HCC) and in healthy controls,using Sanger sequencing.We also determined the ensemble of extended haplotype in healthy control individuals,including several major histocompatibility complex loci,using sequence specific probes.Haplotype reconstruction was performed using the Arlequin and Phase softwares,and linkage disequilibrium(LD) between histocompatibility loci and HFE gene was performed using the Haploview software.RESULTS The HFE*003 allele was overrepresented(f = 71%) and HFE*001 allele was underrepresented(f = 14%) in HH patients compared to all groups.A strong linkage disequilibrium was observed among the H63 D-G,IVS2(+4)-C and C282 YG gene variants,particularly in HH;however,the mutation IVS2(+4)T>C was not directly associated with HH susceptibility.The HFE*001/HFE*002 genotype conferred susceptibility to HCC in HCV patients exhibiting IO(P = 0.02,OR =14.14).Although HFE is telomeric to other histocompatibility genes,the H63 DG/IVS2(+4)-C(P ≤ 0.00001/P ≤ 0.0057) combination was in LD with HLA-B*44 allele group in healthy controls.No LD was observed between HFE alleles and other major histocompatibility loci.CONCLUSION A differential HFE association was observed for HH and for diseases associated with acquired IO(HCV,HCC).Since HFE is very distant from other histocompatibility loci,only weak associations were observed with these alleles.

HFE Gene Mutation Associated with the Severity of Gestational Diabetes Mellitus in Belarusian Women

To determine whether the H63D and C282Y mutations in HFE (hemochromatosis) gene are associated with the risk of gestational diabetes mellitus (GDM), we conducted the study of 65 incident cases. The class of gestational diabetes (A1, A2, B) in pregnant women was defined based on the results of glycemic profile and 75-g oral glucose tolerance test. Two single nucleotide polymorphisms (H63D and C282Y) in HFE gene were genotyped by PCR and RFLP (Restriction Fragment Length Polymorphism). The frequencies of mutations in patients cohort were: 0.14 for H63D and 0.02 for C282Y, which are similar to the data reported for Belarusian population (0.16 and 0.04 respectively). The detailed analysis of case subjects indicated association of H63D mutation with the severity of gestational diabetes mellitus. In the frequencies of H63D mutation and genotypes between the case subjects with A1 and B gestational diabetes were detected significant differences. Our data indicated that the presence of H63D mutation in pregnant women with GDM aggravates the disease—odds ratio 7.4 (95% CI 1.8 - 30.5). Women with gestational diabetes have severe increased risk for illness progressing to class B if they are H63D mutation carriers.

An association study of HFEgene mutation with idiopathic male infertility in the Chinese Han population

Mutations in the haemochromatosis gene （HFE） influence iron status in the general population of Northern Europe, and excess iron is associated with the impairment of spermatogenesis. The aim of this study is to investigate the association between three mutations （C282Y, H63D and S65C） in the HFEgene with idiopathic male infertility in the Chinese Han population. Two groups of Chinese men were recruited： 444 infertile men （including 169 with idiopathic azoospermia） and 423 controls with proven fertility. The HFEgene was detected using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） technique. The experimental results demonstrated that no C282Y or $65C mutations were detected. Idiopathic male infertility was not significantly associated with heterozygous H63D mutation （odds ratio=O.801, 95% confidence interval=0.452-1.421, X2=0.577, P=0.448）. The H63D mutation frequency did not correlate significantly with the serum luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and testosterone （T） levels in infertile men （P=0.896, P=0.404 and P=O.05, respectively）. Our data suggest that the HFEH63D mutation is not associated with idiopathic male reproductive dysfunction.

HFE基因突变在我国成年男性人群的分布

目的:了解遗传性血色素沉积症(HFE)基因突变在铁过量人群和铁营养状况正常人群的分布,探讨HFE基因突变对我国成年男性铁过量状况的影响。方法:从2002年中国居民营养与健康状况调查采集的静脉血液样本中随机抽取226名铁营养状况正常的成年男性作为正常对照组,331名铁过量的成年男性作为铁过量组,比较两组人群HFE基因C282Y突变、H63D突变和S65C突变的分布。结果:在铁过量组,正常基因型占90.03%,H63D突变纯合子占0.60%,H63D突变杂合子占9.07%,S65C突变杂合子占0.30%,未检测到C282Y突变杂合和纯合基因型。在正常对照组,正常基因型占94.25%,H63D突变杂合子占5.75%,未检测到S65C突变和C282Y突变。结论:HFE基因突变不是造成我国成年男性铁过量的主要原因。

Prevalence of HFE mutations and relation to serum (?)ron status in patients with chronic hepatitis C and patients with nonalcoholic fatty liver disease in Taiwan

AIM: To assess the prevalence of the two mutations, C282Y and H63D of HFE gene, in healthy subjects, patients with chronic hepatitis C (CHC), and patients with nonalcoholic fatty liver disease (NAFLD) in Taiwan and to explore the contribution of the HFE mutation on serum iron stores in CHC and NAFLD groups.METHODS: We examined C282Y and H63D mutations of HFE gene in 125 healthy subjects, 29 patients with CHC,and 33 patients with NAFLD. The serum iron markers,including ferritin, iron, and total iron binding capacity (TIBC),were assessed in all patients.RESULTS: All of the healthy subjects and patients were free from C282Y mutation. The prevalence of H63D heterozygosity was 4/125 (3.20%) in healthy subjects, 2/29(6.90%) in CHC group, and 1/33 (3.03%) in NAFLD group.The healthy subjects showed no significant difference in the prevalence of H63D mutation as compared with the CHC or NAFLD group. Increased serum iron store was found in 34.48% of CHC patients and 36.36% of NAFLD patients.In three patients of H63D heterozygosity, only one CHC patient had increased serum iron store. There was no significant difference in the prevalence of HFE mutations between patients with increased serum iron store and those without in CHC or NAFLD group.CONCLUSION: The HFE mutations may not contribute to iron accumulation in the CHC or NAFLD group even when serum iron overload is observed in more than one-third of these patients in Taiwan.

中国河南汉族人HFE C282Y基因突变频率调查

目的调查中国河南汉族人遗传性血色素沉着症HFE C282Y基因突变情况。方法利用聚合酶链反应和限制性片段长度多态性分析方法,检测518例健康献血的河南汉族人血液标本。结果C282Y突变未见。结论中国河南汉族人HFE C282Y等位基因突变频率与美国密歇根州高加索人差异具有统计学意义。

HFE基因多态性检测判断慢性丙型肝炎患者疾病活动的价值

目的观察遗传性血色素沉着症候选基因HFE多态性检测判断CHC疾病活动的价值。方法2016年11月~2018年11月我院收治的257例丙型肝炎病毒感染者,其中病毒感染者131例和慢性丙型肝炎(CHC)患者126例。采用酶结合免疫吸附法测定血清铁蛋白(SF)水平,使用ABIPrismsTM-7900实时荧光定量PCR仪和TaqMan-MGB荧光探针,以实时定量PCR法检测HFE基因rs2071303和rs9366637位点基因型。结果病毒感染者SF水平为(97.5±4.1)μg/L,显著低于CHC患者[(202.1±24.5)μg/L,P<0.05],血清ALT水平为(34.0±4.5)U/L,显著低于CHC患者[(88.4±5.6)U/L,P<0.05],AST为(37.5±4.2)U/L,显著低于CHC患者[(70.0±5.4)U/L,P<0.05];病毒感染者HCV基因非Ⅰb型频率为29.8%,显著高于CHC患者13.5%(P<0.05),病毒感染者HCV基因型中混合型频率为9.1%,显著低于CHC患者的21.4%(P<0.05);病毒感染者rs2071303位点GG基因型患者SF水平为(97.6±4.2)μg/L,显著低于CHC患者[(199.5±45.4)μg/L,P<0.05],GA基因型SF水平为(97.6±4.1)μg/L,显著低于CHC患者[(207.5±34.7)μg/L,P<0.05],AA基因型SF水平为(96.7±3.7)μg/L,显著低于CHC患者[(198.0±44.8)μg/L,P<0.05];病毒感染者rs9366637位点TT基因型患者SF水平为(97.4±4.0)μg/L,显著低于CHC患者[(206.4±35.6)μg/L,P<0.05],TC基因型SF水平为(97.2±4.0)μg/L,显著低于CHC患者[(208.5±34.0)μg/L,P<0.05],CC基因型SF水平为(99.1±4.5)μg/L,显著低于CHC患者[(178.5±58.6)μg/L,P<0.05];病毒感染者rs2071303位点AA基因型频率为13.7%,显著低于CHC患者的21.4%(P<0.05),病毒感染者AC单倍型频率为3.1%,显著低于CHC患者的8.3%(P<0.05)。结论HFE基因多态性与CHC疾病活动密切相关,临床应引起足够的重视。

地中海贫血铁过载与HFE基因突变的研究进展

地中海贫血是一种常见的常染色体隐性遗传病,是由某个或多个珠蛋白基因异常引起一种或一种以上珠蛋白肽链合成减少或缺乏的溶血性贫血。地中海贫血长期的慢性溶血、贫血状态导致人体出现铁过载情况,从而引起心脏、肝脏、内分泌腺体、骨骼等多个组织器官功能障碍。已有相关研究表明HFE基因突变与地中海贫血铁代谢情况相关,本文主要从HFE基因突变机制、HFE突变基因与地中海贫血铁过载的关系来阐述H63D、C282Y和S65C三种类型HFE基因突变在地中海贫血中的研究进展,为后续祛铁治疗提供新的诊疗思路。

遗传性血色病突变基因与糖代谢紊乱的关系研究

目的检测2例遗传性血色病患者HFE基因突变情况,初步观察HFE基因突变与糖代谢紊乱的关系。方法采集患者外周血提取基因组DNA,针对常见HFE基因突变区域设计引物进行PCR,测序后分析基因序列;构建野生型和突变型HFE基因表达载体,转染L02细胞检测胰岛素信号通路及下游有关糖代谢关键酶的表达水平。结果 2例患者均为C282YA/A纯合突变,无H63D/S65C突变;过表达突变型HFE基因的细胞Akt磷酸化水平较弱,6-磷酸果糖激酶-1表达水平下调而磷酸烯醇式丙酮酸羧激酶和葡萄糖-6-磷酸酶表达水平上调。结论 HFE基因C282Y突变可能与患者的糖代谢紊乱有关。

Fatty liver in H63D homozygotes with hyperferritinemia

To study the clinical correlates of the H63D mu-tation we have analysed the phenotype of H63D homozygotes identified through mutation analysis in a referral laboratory. A total of 366 blood samples referred for lIFE analysis were screened for C282Y and H63D mutations. Four H63D homozygotes were identified. All had raised serum ferritin but normal transferrin saturation. They were negative for hepatitis B and C and only one patient consumed excess alcohol. In all 4 cases ultrasonography revealed fatty liver. In two patients a liver biopsy was done and showed mild siderosis with an unusual distribution and macrovesicular steatosis. These data confirm the association between fatty liver, hyperferritinaemia and increased hepatic iron, but do not clarify whether siderosis was related to steatosis rather than homozygosity for the H63D mutation. Patients with fatty liver may complicate the interpretation of data in population studies of the expression of H63D homozygosity.

The Hemochromatosis Distribution in Matera Province： A New SNP to Explain the Low Genotype-Phenotype Correlation

The present study aims to investigate the genotype-phenotype correlation of the hereditary hemochromatosis （HH）, a genetic disorder of iron metabolism, in Matera province （Basilicata, Italy）. Integrating both epidemiological and molecular approaches, the authors studied： （a） the frequency of the HH main mutations; （b） the association between mutations and HH cases. The majority of patients with HH are homozygous for the C282Y mutation of the HFE gene. A second mutation （H63D） is more widely distributed and its connection with HH isn＇t clear, but a low penetrance is attributed to this variant. The population-based study consists of three steps： （1） determination of iron biochemical parameters, （2） genetic test, and （3） sequencing of HFE gene and bioinformatics studies. A case report is presented in a 41-year-old male （genotype： H63D/wt） with biochemical and clinical evidences of HH, in absence of secondary iron overload factors. In the cohort of studied patients （150M：62F）, there are 18 homozygous patients; H63D/H63D genotype is found in 11 cases. In the heterozygous group, H63D/wt is the predominant genotype （61/68 subjects）. All the H63D/wt residents in the same village （Mont.） show altered biochemical parameter levels. In our case study, a substitution localized into the HFE promoter （nt225A 〉 C） is found. Results show that the H63D genotype is responsible for most cases of HH. The peculiar clinical manifestation found in Mont. suggests a founder effect. In our case, the iron overload is related to a presence of an undetected mutation, critical for the transcriptional regulation of the HFE gene.

Lymphocyte subsets in alcoholic liver disease

AIM:To compare lymphocyte subsets between healthy controls and alcoholics with liver disease.METHODS:The patient cohort for this study included individuals who were suspected to have alcoholic liver disease(ALD) and who had undergone liver biopsy(for disease grading and staging,doubts about diagnosis,or concurrent liver disease;n = 56).Normal controls included patients who were admitted for elective cholecystectomy due to non-complicated gallstones(n = 27).Formalin-fixed,paraffin-embedded liver biopsy specimens were sectioned and stained with hematoxylin and eosin and Perls' Prussian blue.The non-alcoholic steatohepatitis score was used to assess markers of ALD.Lymphocyte population subsets were determined by flow cytometry.T lymphocytes were identified(CD3+),and then further subdivided into CD4+ or CD8+ populations.B lymphocytes(CD19+) and natural killer(NK) cell numbers were also measured.In addition to assessing lymphocyte subpopulation differences between ALD patients and controls,we also compared subsets of alcoholic patients without cirrhosis or abstinent cirrhotic patients to normal controls.RESULTS:The patient cohort primarily consisted of older men.Active alcoholism was present in 66.1%.Reported average daily alcohol intake was 164.9 g and the average lifetime cumulative intake was 2211.6 kg.Cirrhosis was present in 39.3% of the patients and 66.1% had significant fibrosis(perisinusoidal and portal/periportal fibrosis,bridging fibrosis,or cirrhosis) in their liver samples.The average Mayo end-stage liver disease score was 7.6.No hereditary hemochromatosis genotypes were found.ALD patients(n = 56) presented with significant lymphopenia(1.5 × 109/L ± 0.5 × 109/L vs 2.1 × 109/L ± 0.5 × 109/L,P < 0.0001),due to a decrease in all lymphocyte subpopulations,except for NK lymphocytes:CD3+(1013.0 ± 406.2/mm3 vs 1523.0 ± 364.6/mm3,P < 0.0001),CD4+(713.5 ± 284.7/mm3 vs 992.4 ± 274.7/mm3,P < 0.0001),CD8+(262.3 ± 140.4/mm3 vs 478.9 ± 164.6/mm3,P < 0.0001),and CD19+(120.6 ± 76.1/mm3 vs 264.6 ± 88.0/mm3,P < 0.0001).CD8+ lymphocytes suffered the greatest reduction,as evidenced by an increase in the CD4+/CD8+ ratio(3.1 ± 1.3 vs 2.3 ± 0.9,P = 0.013).This ratio was associated with the stage of fibrosis on liver biopsy(rs = 0.342,P = 0.01) and with Child-Pugh score(rs = 0.482,P = 0.02).The number of CD8+ lymphocytes also had a positive association with serum ferritin levels(rs = 0.345,P = 0.009).Considering only patients with active alcoholism but not cirrhosis(n = 27),we found similar reductions in total lymphocyte counts(1.8 × 109/L ± 0.3 × 109/L vs 2.1 × 109/L ± 0.5 × 109/L,P = 0.018),and in populations of CD3+(1164.7 ± 376.6/mm3 vs 1523.0 ± 364.6/mm3,P = 0.001),CD4+(759.8 ± 265.0/mm3 vs 992.4 ± 274.7/mm3,P = 0.003),CD8+(330.9 ± 156.3/mm3 vs 478.9 ± 164.6/mm3,P = 0.002),and CD19+(108.8 ± 64.2/mm3 vs 264.6 ± 88.0/mm3,P < 0.0001).In these patients,the CD4+/CD8+ ratio and the number of NK lymphocytes was not significantly different,compared to controls.Comparing patients with liver cirrhosis but without active alcohol consumption(n = 11),we also found significant lymphopenia(1.3 × 109/L ± 0.6 × 109/L vs 2.1 × 109/L ± 0.5 × 109/L,P < 0.0001) and decreases in populations of CD3+(945.5 ± 547.4/mm3 vs 1523.0 ± 364.6/mm3,P = 0.003),CD4+(745.2 ± 389.0/mm3 vs 992.4 ± 274.7/mm3,P = 0.032),CD8+(233.9 ± 120.0/mm3 vs 478.9 ± 164.6/mm3,P < 0.0001),and CD19+(150.8 ± 76.1/mm3 vs 264.6 ± 88.0/mm3,P = 0.001).The NK lymphocyte count was not significantly different,but,in this group,there was a significant increase in the CD4+/CD8+ ratio(3.5 ± 1.3 vs 2.3 ± 0.9,P = 0.01).CONCLUSION:All patient subsets presented with decreased lymphocyte counts,but only patients with advanced fibrosis presented with a significant increase in the CD4+/CD8+ ratio.

HFE基因与遗传性血色素沉着症

HFE基因发现于 1996年 ,属于 HL A 类样基因 ,是遗传性血色素沉着症候选基因。HFE分子的功能可能是参与调节转铁蛋白与转铁蛋白受体间的相互作用。遗传性血色素沉着症是一种常染色体隐性遗传性铁异常沉积性疾病 ,高加索群体中发病率高 ,平均不到 30 0人就有一个是该病患者。大量群体遗传学研究结果 ,提示 HFE基因 C2 82 Y突变与遗传性血色素沉着症显著相关 ,HFE H6 3D突变对遗传性血色素沉着症影响较小。新近发现 ,HFE分子通过与转铁蛋白受体反应影响转铁蛋白与转铁蛋白受体间的相互作用 ,从而调节体内铁平衡。 C2 82 Y突变可使 HFE分子不能与β2微球蛋白结合 ,不能转运到细胞表面 ,从而失去对转铁蛋白和转铁蛋白受体作用的调节功能。H6 3D突变影响功能的机理目前尚不清楚 ,现有研究提示 H6 3D突变蛋白可与β2微球蛋白结合 ,并转运到细胞表面 ,突变对分子功能的影响可能也表现在不能调节转铁蛋白和转铁蛋白受体间的作用。

HFE基因多态与云南汉族、彝族和哈尼族原发性高血压的关联研究

目的:探讨血色沉着病基因(hemochromatosis,HFE)标签单核苷酸多态(tag single nucleotide polymorphism,tag SNPs)与云南汉族、彝族和哈尼族原发性高血压发病的关联性。方法:采用病例-对照关联研究策略,运用聚合酶链式反应-限制性片段长度多态方法,对云南940例汉族人、598例彝族人和661例哈尼族人进行HFE基因5个标签SNPs(rs9366637、rs1799945、rs2071303、rs1800758、rs2858996)的多态进行检测。结果:检测到rs9366637位点在不同民族人群与高血压发病的关联性结果不一致。汉族整体人群和男性人群中,发现rs9366637位点C等位基因和CC基因型是高血压发病的风险因子;而在哈尼族混合和女性人群,发现该位点T等位基因和TT基因型是高血压发病的风险因子;在彝族人群,未发现rs9366637位点多态与高血压发生相关。此外,发现rs2858996T等位基因和TT基因型在汉族整体和男性人群是高血压发病的保护因子。结论:HFE基因rs9366637和rs2858996位点可能是云南汉族和哈尼族高血压发生的易感标记,在云南汉族和哈尼族人群中值得关注。

中国健康正常人、骨髓增生异常综合征及再生障碍性贫血患者HFE基因突变的研究

目的分析健康正常人、骨髓增生异常综合征（MDS）和再生障碍性贫血（AA）患者HFE基因突变的频率并探讨其与铁代谢和铁过载脏器功能受损相关指标的关系。方法采用聚合酶链反应-限制性片段长度多态性（PCR—RFLP）联合测序分析的方法检测271例MDS患者、402例AA患者和1615名健康正常对照的HFE基因H63D和C282Y突变，并比较未输注红细胞的MDS和AA患者HFE基因突变组与未突变组的铁代谢指标和铁过载脏器功能受损相关指标。结果271例MDS患者、402例AA患者及1615名正常对照中均未发现HFE基因C282Y突变及C282Y和H63D复合突变。MDS患者H63D突变率为4．1％（271例中11例），且均为杂合型。AA患者H63D杂合型突变率为9．7％（402例中39例），纯合型突变率0．25％（402例中1例）。正常对照H63D杂合型突变率为10．2％（164例），纯合型突变率0．24％（4例）。MDS患者H63D突变率明显低于正常对照（P=0．002），而AA患者与正常对照比较差异无统计学意义（P=0．988）。未输注红细胞的MDS及AA患者的血清铁蛋白（SF）值、血清铁（SI）值、铁饱和度（TS）值均接近或高于正常高限，血清未饱和铁（UIBC）值明显低于正常。未输注红细胞的MDS患者H63D突变组与未突变组的SF、SI、UIBC、总铁结合力（TIBC）、TS值差异无统计学意义（P值均〉0．05）；未输注红细胞的AA患者H63D突变组的SI值明显高于未突变组[42．6（24．6～60．4）μmol／L和32．0（8．4—63．3）μmol／L（P=0．011）]，而两组的其他铁代谢参数差异均无统计学意义（P值均〉0．05）。MDS及AA患者或就诊前未输注红细胞的MDS及AA患者H63D突变组与未突变组的肝酶值、空腹血糖（FBS）值、心电图（ECG）异常率、外周血指标差异均无统计学意义（P值均〉0．05）。结论HFE基因H63D和C282Y突变在人群的分布有种族和遗传的差异，中国人HFE基因的突变率明显低于白种人。MDS与AA患者本身均可致铁过载，HFE基因H63D和C282Y突变并不是导致其铁过载的主要原因。