Liver Cirrhosis in Chronic Hepatitis B Patients Is Associated with Genetic Variations in DNA Repair Pathway Genes.

Liver cirrhosis (LC), contributing to more than 1 million of deaths annually, is a major healthcare concern worldwide. Hepatitis B virus (HBV) is a major LC etiological factor, and 15% of patients with chronic HBV infection (CHB) develop LC within 5 years. Recently, novel host genetic determinants were shown to influence HBV lifecycle and CHB course. DNA repair enzymes can affect dynamics of liver damage and are involved in HBV covalently closed circular DNA (cccDNA) formation, an essential step for viral replication. This study aimed to evaluate the possible role of genes representing key DNA-repair pathways in HBV-induced liver damage. MALDI-TOF MS genotyping platform was applied to evaluate variations within XRCC1, XRCC4, ERCC2, ERCC5, RAD52, Mre11, and NBN genes. Apart from older age (p < 0.001), female sex (p = 0.021), portal hypertension (p < 0.001), thrombocytopenia (p < 0.001), high HBV DNA (p = 0.001), and high aspartate aminotransferase (AST) (p < 0.001), we found that G allele at rs238406 (ERCC2, p = 0.025), T allele at rs25487 (XRCC1, p = 0.012), rs13181 GG genotype (ERCC2, p = 0.034), and C allele at rs2735383 (NBN, p = 0.042) were also LC risk factors. The multivariate logistic regression model showed that rs25487 CC (p = 0.005) and rs238406 TT (p = 0.027) were independently associated with lower risk of LC. This study provides evidence for the impact of functional and potentially functional variations in key DNA-repair genes XRCC1 and ERCC2 in HBV-induced liver damage in a Caucasian population.

Genetic variation in IL-10 influences the progression of hepatitis B infection.

OBJECTIVES: The outcomes of hepatitis B virus (HBV) infection vary substantially among affected individuals, providing evidence of the role of host genetic background in the susceptibility to HBV persistence and the dynamics of liver injury progression to cirrhosis and hepatocellular carcinoma (HCC). METHODS: Six single-nucleotide polymorphisms within the interleukin 10 gene (IL10) were genotyped by MALDI-TOF mass spectrometry in 857 patients with chronic HBV infection (CHB), 48 patients with resolved HBV infection, and 100 healthy volunteers. Associations of the selected polymorphisms with susceptibility to chronic HBV infection, liver injury progression, and outcomes were investigated. RESULTS: IL10 -819T (rs1800871), -592A (rs1800872), and +504T (rs3024490) alleles were associated with treatment-induced hepatitis B surface antigen (HBsAg) seroclearance. Additionally, IL10 ATAC haplotype increased the chance of HBsAg loss and was significantly more frequent in patients with less liver injury. Moreover rs1800871TT, rs1518110TT, rs1800872AA, and rs3024490TT genotypes were identified as predictors of a lower FIB-4 score (<0.5). CONCLUSIONS: This study indicates that polymorphisms within the promoter region and intronic sequences of IL10 are associated with chronicity of hepatitis B and with HBV-induced liver damage.

Host genetic background affects the course of infection and treatment response in patients with chronic hepatitis B.

BACKGROUND: Hepatitis B virus (HBV) utilizes proteins encoded by the host to infect hepatocytes and replicate. Recently, several novel host factors have been identified and described as important to the HBV lifecycle. The influence of host genetic background on chronic hepatitis B (CHB) pathogenesis is still poorly understood. OBJECTIVES: Here, we aimed to investigate the association of NTCP, FXRα, HNF1α, HNF4α, and TDP2 genetic polymorphisms with the natural course of CHB and antiviral treatment response. STUDY DESIGN: We genotyped 18 single-nucleotide polymorphisms using MALDI-TOF mass spectrometry in 136 patients with CHB and 100 healthy individuals. We investigated associations of the selected polymorphisms with biochemical, serological and hepatic markers of disease progression and treatment response. RESULTS: No significant differences in genotypic or allelic distribution between CHB and control groups were observed. Within TDP2, rs3087943 variations were associated with treatment response, and rs1047782 modified the risk of advanced liver inflammation. Rs7154439 within NTCP was associated with HBeAg seroconversion after 48 weeks of nucleos(t)ide analogue treatment. HNF1α genotypes were associated with treatment response, liver damage and baseline HBeAg presence. HNF4α rs1800961 predicted PEG-IFNα treatment-induced HBsAg clearance in long-term follow up. CONCLUSIONS: This study indicates host genetic background relevance in the course of CHB and confirms the role of recently described genes for HBV infection. The obtained results might serve as a starting point for validation studies on the clinical application of selected genetic variants to predict individual risks of CHB-induced liver failure and treatment response.

TNF-α polymorphisms affect persistence and progression of HBV infection.

BACKGROUND: Hepatitis B virus (HBV) infections are a major threat worldwide. Disease progression and outcome is diverse and depends on host genetic background. Recently, a high rate of HBV reactivation in individuals receiving tumor necrosis factor-α (TNF-α) antagonists showed the importance of this cytokine in HBV infection control. Here, we investigated the influence of TNF-α promoter polymorphisms on susceptibility to chronic HBV infection (CHB), liver injury progression and outcomes. METHODS: A total of 231 patients with CHB constituted the study group and 100 healthy volunteers-the local control group. TNF-α -1031T/C, -863C/A, -857C/T, -308G/A, and -238G/A were genotyped using MALDI-TOF mass spectrometry. RESULTS: TNF-α -1031C and -863A alleles were observed more frequently in CHB group than in healthy controls. Carriers of TNF-α -1031C and -863A variant alleles had lower baseline levels of serum HBV DNA and lower liver necroinflammatory activity than dominant homozygotes. A -857CT genotype predisposed to higher necroinflammatory activity. No associations between TNF-α variants and liver fibrosis were found. CONCLUSION: This study indicates that TNF-α -863A and -1031C alleles are associated with increased susceptibility to CHB in individuals from northern Poland. The same variants determine the course of CHB, lowering viremia and reducing necroinflammatory activity of the liver.

Differences in sequences between HBV-relaxed circular DNA and covalently closed circular DNA.

The hepatitis B virus (HBV) genome exists in two forms: circular covalently closed DNA (cccDNA) and relaxed circular DNA (RCDNA). Here, we investigated the presence of differences in the sequences of both forms in paired samples of serum and liver tissue. The serum and liver biopsy samples were collected at the same time from 67 chronically infected patients. The genotyping of the RCDNA and cccDNA was performed using mass spectrometry analysis. The HBV mutations located in the HBV pol (P) and the HBV basal core promoter/pre-core (BCP/PC) regions were included. The BCP/PC and P sequences of the RCDNA extracted from liver and blood samples were different in 39% and 16% of patients, respectively. Differences were also found between RCDNA and cccDNA extracted from the same liver specimen. Moreover, the cccDNA BCP/PC region sequence had an impact on various virological and clinical parameters. We demonstrated that there are differences between the RCDNA and cccDNA sequences that were extracted from the same liver tissue. However, further investigations are needed to analyze whether the mutations in the cccDNA are conserved and whether cccDNA serves as a 'mutation storage' pool for HBV. This result could have profound implications for the subsequent therapy choices for treatment-experienced patients.

Association between uridin diphosphate glucuronosylotransferase 1A1 (UGT1A1) gene polymorphism and neonatal hyperbilirubinemia.

OBJECTIVE: To assess the prevalence of UGT1A1*28 and UGT1A1*60 polymorphisms of UGT1A1 gene and their association with hyperbilirubinemia. STUDY DESIGN: The study was performed at a single centre - at the Department of Obstetrics of the Medical University of Gdansk in Poland. DNA was isolated from Guthrie cards of 171 infants. Only full term newborns (gestational age 38-42 weeks) were included in the study. Fluorescent molecular probes were used for UGT1A1 promoter variation analysis. The presence of UGT1A1*28 polymorphism was detected with a dual-probe system, and UGT1A1*60 with a SimpleProbe™. RESULT: Homozygous UGT1A1*28 and UGT1A1*60 genotypes were detected in 14.6% and 20.5% of the newborns, respectively. Homozygous (G/G) genotypes of UGT1A1*60 polymorphism were found in all of the UGT1A1*28 (i.e. (TA)7/(TA)7) homozygotes. More than 80% (55/66) of the children with "wild" type UGT1A1*28 genotype (where no polymorphism was detected) (i.e. (TA)6/(TA)6) carried the "wild" (T/T) genotype of UGT1A1*60 as well. The UGT1A1*28 polymorphism was detected more often among neonates with elevated bilirubin. Hyperbilirubinemia was diagnosed more frequently in boys. CONCLUSION: Polymorphisms of the UGT1A1 gene frequently co-exist in neonates. The presence of UGT1A1*28 polymorphism and male gender seem to predispose to neonatal hyperbilirubinemia.

Interferon lambda polymorphisms associate with body iron indices and hepatic expression of interferon-responsive long non-coding RNA in chronic hepatitis C.

Single nucleotide polymorphisms (SNPs) within DNA region containing interferon lambda 3 (IFNL3) and IFNL4 genes are prognostic factors of treatment response in chronic hepatitis C (CHC). Iron overload, frequently diagnosed in CHC, is associated with unfavorable disease course and a risk of carcinogenesis. Its etiology and relationship with the immune response in CHC are not fully explained. Our aim was to determine whether IFNL polymorphisms in CHC patients associate with body iron indices, and whether they are linked with hepatic expression of genes involved in iron homeostasis and IFN signaling. For 192 CHC patients, four SNPs within IFNL3-IFNL4 region (rs12979860, rs368234815, rs8099917, rs12980275) were genotyped. In 185 liver biopsies, histopathological analyses were performed. Expression of five mRNAs and three long non-coding RNAs (lncRNAs) was determined with qRT-PCR in 105 liver samples. Rs12979860 TT or rs8099917 GG genotypes as well as markers of serum and hepatocyte iron overload associated with higher activity of gamma-glutamyl transpeptidase and liver steatosis. The presence of two minor alleles in any of the tested SNPs predisposed to abnormally high serum iron concentration and correlated with higher hepatic expression of lncRNA NRIR. On the other hand, homozygosity in any major allele associated with higher viral load. Patients bearing rs12979860 CC genotype had lower hepatic expression of hepcidin (HAMP; P = 0.03). HAMP mRNA level positively correlated with serum iron indices and degree of hepatocyte iron deposits. IFNL polymorphisms influence regulatory pathways of cellular response to IFN and affect body iron balance in chronic hepatitis C virus infection.

Association of hepcidin mRNA expression with hepatocyte iron accumulation and effects of antiviral therapy in chronic hepatitis C infection.

BACKGROUND: Iron overload is frequently observed in patients with chronic hepatitis C (CHC) and is associated with the increased risk of liver fibrosis and carcinogenesis. Hepcidin is a regulator of iron homeostasis and a component of innate immunity. Based on experimental studies, iron overload might be a result of low hepcidin synthesis in CHC. OBJECTIVES: The aim of this case-control study was to assess hepcidin mRNA expression in liver tissue of patients with CHC in terms of iron metabolism parameters, hemochromatosis (HFE) gene mutations, disease activity, and efficacy of antiviral treatment with pegylated interferon and ribavirin. PATIENTS AND METHODS: A total of 31 patients with CHC, who were qualified for antiviral therapy, were compared with 19 patients with chronic hepatitis B (CHB). In both groups, liver function tests and serum iron parameters were assayed and hepcidin mRNA expression was measured in liver specimens using real time PCR with normalization to reference genes mRNA of stable expression. RESULTS: Patients with CHC had lower hepcidin mRNA expression and more frequently iron deposits in hepatocytes than subjects with CHB did. In CHC group, hepcidin mRNA expression was positively correlated with alanine aminotransferase activity and serum iron concentration. Low expression of hepcidin had no correlation with tissue iron overload in those with CHC. In univariate analysis, HCV viral load and efficacy of antiviral treatment were not significantly associated with hepcidin mRNA expression. CONCLUSIONS: Further studies on the role of hepcidin in pathogenesis of CHC are needed to assess the potency of its use in antiviral treatment.

Liver steatosis correlates with iron overload but not with HFE gene mutations in chronic hepatitis C.

BACKGROUND: Liver steatosis and iron overload, which are frequently observed in chronic hepatitis C (CHC), may contribute to the progression of liver injury. This study aimed to evaluate the correlation between liver steatosis and iron overload in Polish patients with CHC compared to non-alcoholic fatty liver disease (NAFLD) and HFE-hereditary hemochromatosis (HH) patients. METHODS: A total of 191 CHC patients were compared with 67 NAFLD and 21 HH patients. Liver function tests, serum markers of iron metabolism, cholesterol and triglycerides were assayed. The inflammatory activity, fibrosis, iron deposits and steatosis stages were assessed in liver specimens. HFE gene polymorphisms were investigated by PCR-RFLP. RESULTS: Liver steatosis was associated with obesity and diabetes mellitus. This disease was confirmed in 76/174 (44%) CHC patients, most of whom were infected with genotype 1. The average grade of steatosis was higher in NAFLD patients. CHC patients had significantly higher iron concentrations and transferrin saturations than NAFLD patients. Compared with CHC patients, HH patients had higher values of serum iron parameters and more intensive hepatocyte iron deposits without differences in the prevalence and intensity of liver steatosis. In the CHC group, lipids accumulation in hepatocytes was significantly associated with the presence of serum markers of iron overload. No correlation between the HFE gene polymorphism and liver steatosis in CHC patients was found. CONCLUSIONS: Liver steatosis was diagnosed in nearly half of CHC patients, most of whom were infected with genotype 1. The intensity of steatosis was lower in CHC patients than that in NAFLD patients because of a less frequent diagnosis of metabolic syndrome. Only in CHC patients were biochemical markers of iron accumulation positively correlated with liver steatosis; these findings were independent of HFE gene mutations.

Diagnosis and treatment difficulties in 18-year-old male patient with hereditary hemochromatosis, chronic hepatitis B, Gilbert syndrome and ulcerative colitis.

Among possible causes of chronic hepatitis in adolescents most common are infections, autoimmune disorders and metabolic diseases. Thus, diagnostic procedures should be multidirectional. This study reports diagnosis and treatment difficulties in an 18-year-old male patient with hereditary hemochromatosis (HH), ulcerative colitis (UC), chronic hepatitis B (CHB) and Gilbert syndrome. The presented case illustrates problems in diagnostics related to the presence of numerous disease conditions in one patient. It should be taken into consideration that these diseases coexisting in one patient can mutually affect their symptoms creating specific diagnostic difficulties.

Iron overload and HFE gene mutations in Polish patients with liver cirrhosis.

BACKGROUND: Increased liver iron stores may contribute to the progression of liver injury and fibrosis, and are associated with a higher risk of hepatocellular carcinoma development. Pre-transplant symptoms of iron overload in patients with liver cirrhosis are associated with higher risk of infectious and malignant complications in liver transplant recipients. HFE gene mutations may be involved in the pathogenesis of liver iron overload and influence the progression of chronic liver diseases of different origins. This study was designed to determine the prevalence of iron overload in relation to HFE gene mutations among Polish patients with liver cirrhosis. METHODS: Sixty-one patients with liver cirrhosis included in the study were compared with a control group of 42 consecutive patients subjected to liver biopsy because of chronic liver diseases. Liver function tests and serum iron markers were assessed in both groups. All patients were screened for HFE mutations (C282Y, H63D, S65C). Thirty-six of 61 patients from the study group and all controls had liver biopsy performed with semiquantitative assessment of iron deposits in hepatocytes. RESULTS: The biochemical markers of iron overload and iron deposits in the liver were detected with a higher frequency (70% and 47% respectively) in patients with liver cirrhosis. There were no differences in the prevalence of all HFE mutations in both groups. In patients with a diagnosis of hepatocellular carcinoma, no significant associations with iron disorders and HFE gene mutations were found. CONCLUSIONS: Iron disorders were detected in patients with liver cirrhosis frequently but without significant association with HFE gene mutations. Only the homozygous C282Y mutation seems to occur more frequently in the selected population of patients with liver cirrhosis. As elevated biochemical iron indices accompanied liver iron deposits more frequently in liver cirrhosis compared to controls with chronic liver disease, there is a need for more extensive studies searching for the possible influence of non-HFE iron homeostasis regulators and their modulation on the course of chronic liver disease and liver cirrhosis.

The role of iron overload and HFE gene mutations in the era of pegylated interferon and ribavirin treatment of chronic hepatitis C.

BACKGROUND: Iron overload observed in chronic hepatitis C (CHC) has been suggested to be one of the negative prognostic factors influencing liver disease progression and failure of treatment with recombinant interferon in monotherapy or in combination with ribavirin. The aim of this study was to assess occurrence of iron overload in relation to polymorphism of the HFE and the influence of both these factors on efficacy of antiviral treatment with pegylated interferon and ribavirin in patients with CHC. MATERIAL/METHODS: Liver function tests, serum indices of iron metabolism, and HFE mutations were assayed in 152 patients with CHC from Poland. Histopathological examination of the liver biopsy specimen was performed in 138 patients. Sixty-one patients were treated with pegylated interferon alfa-2 and ribavirin. The comparative analysis was performed in 2 groups of patients: those with and those without elevated serum indices of iron metabolism. RESULTS: Increased biochemical iron metabolism parameters correlated with older age, higher ALT activity, more advanced liver fibrosis and treatment failure. Iron deposits in liver specimens were not accompanied by exacerbation of necro-inflammatory activity and advanced fibrosis. Elevated biochemical values of iron metabolism parameters and presence of hepatic iron deposits correlated positively with C282Y mutations. The lack of sustained viral response after treatment with pegylated interferon and ribavirin was observed more frequently in carriers of HFE mutations. CONCLUSIONS: Iron overload was frequently detected in patients with CHC, and was associated only with C282Y alleles. Biochemical markers of iron overload and HFE gene mutations were negative prognostic factors of antiviral treatment.

The role of MR imaging in detection of hepatic iron overload in patients with cirrhosis of different origins.

BACKGROUND: There are many pathological conditions with hepatic iron overload. Classical definite diagnostic methods of these disorders are invasive and based on a direct tissue biopsy material. For the last years the role of MR imaging in liver diagnostics has been increasing. MRI shows changes of liver intensity in patients with hepatic iron overload. Changes in MR signal are an indirect consequence of change of relaxation times T2 and T2*, that can be directly measured. The purpose of the study was to evaluate usefulness of MR imaging in the detection of hepatic iron overload in patients with cirrhosis of different origins. METHODS: MR imaging at 1.5T was prospectively performed in 44 patients with liver cirrhosis who had undergone liver biopsy with histopathological assessment of hepatic iron deposits. In all patients the following sequences were used: SE, Express, GRE in T2 and T1-weighted images. Signal intensity (SI) was measured on images obtained with each T2 weighted sequence by means of regions of interest, placed in the liver and paraspinal muscles. The correlation between iron overload, histopathological score, serum ferritin and SI ratio was analyzed. RESULTS: In 20 patients with iron overload confirmed by the biopsy, the liver parenchyma demonstrated lower signal intensity than that of paraspinal muscles. This effect was visible only in 8 patients with hepatic iron overload in Express T2-weighted images. Higher signal intensity of liver than that of skeletal muscles on GRE - T2 weighted images was noted in 24 patients with cirrhosis and without elevated hepatic iron concentration. We observed a correlation between low and high iron concentration and liver to muscle SI ratio. CONCLUSION: MR imaging is a useful and fast noninvasive diagnostic tool for the detection of liver iron overload in patients with cirrhosis of different origins.Liver to muscle SI ratio in GRE-T2-weighted sequence facilitates to differentiate patients with low and high degree of hepatic iron overload, which correlates with the origin of liver cirrhosis.

UGT1A1 gene polymorphism as a potential factor inducing iron overload in the pathogenesis of type 1 hereditary hemochromatosis.

Aim Hereditary hemochromatosis is a common genetic disorder characterized by iron overload and subsequent organ damage. It is caused in most cases by HFE gene mutations which penetrance can be affected by many factors. The aim of this study was to establish the role of UGT1A1 gene polymorphism and serum bilirubin concentration in the pathogenesis of hereditary hemochromatosis. Methods Biochemical, histopathological and genetic data indicating iron excess and serum total bilirubin concentration were determined in 32 patients with the type 1 hereditary hemochromatosis. Fluorescent molecular probes assays were used for genotyping of UGT1A1*28 and UGT1A1*60 mutations in these individuals. Results High incidence and a significant correlation of UGT1A1 gene mutations with increased serum bilirubin level and lower grades of liver tissue inflammatory activity were observed in study participants. UGT1A1*28 and UGT1A1*60 mutations were strongly linked together. Two of the subjects presented very rare genotypes of UGT1A1 gene: (TA)(5/7) and c.-64G>C heterozygotes. Conclusions UGT1A1 gene polymorphism and as its consequence of high serum bilirubin level may promote iron accumulation in hemochromatosis patients by reducing the activity of inflammation. We proposed a possible mechanism of this interaction.

Could iron deposits in hepatocytes serve as a prognostic marker of HFE gene mutations?

BACKGROUND/AIMS: The diagnosis of hereditary hemochromatosis (HH) is based on qualitative measurement of tissue iron concentration and genetic tests. The aim of this study was to evaluate the correlation between the presence of iron deposits in the liver and the HFE gene mutations in patients with chronic liver diseases (CLD). METHODOLOGY: The 182 patients, age range 18-71 years, were hospitalized in Gdansk because of CLD. The C282Y, H63D and S65C HFE mutations were screened by PCR-RFLP analysis. Liver function tests, serological examinations for viral hepatitis, serum iron and ferritin concentration and semiquantitative assessment of liver iron were done in all subjects. Patients were divided into Group A without iron deposits in the liver, and Group B with deposits. The most frequent etiology of CLD was chronic hepatitis C. RESULTS: Biochemical parameters indicating iron storage and ALT activity were significantly higher in Group B. Either typical for diagnosis HH homozygotes C282Y/C282Y and combined heterozygotes C282Y/H63D or carriers of other HFE gene mutations were found significantly more frequently in Group B. CONCLUSIONS: The finding of iron deposits in routinely obtained liver specimen correlates with occurrence of the different HFE gene mutations.

GUS and PMM1 as suitable reference genes for gene expression analysis in the liver tissue of patients with chronic hepatitis.

BACKGROUND: The proper application of quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) for the relative quantification of a target gene in gene profiling studies requires reference genes to normalize sample variations. Stable housekeeping genes for this purpose have never been investigated in the liver tissue of patients with chronic hepatitis. MATERIAL/METHODS: Expression profiles of six functionally distinct housekeeping genes (ACTB, CYCC, GUS, HPRT1, PMM1, POLR2L) were examined by RT-PCR in liver specimens from 12 individuals with chronic hepatitis C or B. Two software programs, geNorm and NormFinder, were used to assess the expression stability of the studied genes. RESULTS: Crossing-point values of the candidate reference genes were recorded between 22 and 28. In three groups of patients (all patients, HCV patients, HBV patients) both programs identified GUS as the most stably expressed housekeeping gene (stability values: 0.275-0.360 and 0.095-0.107 determined by geNorm and NormFinder, respectively), followed by PMM1 (0.275-0.360 and 0.168-0.227), and POLR2L (0.347-0.397 and 0.319-0.388). CONCLUSIONS: The genes GUS and PMM1 are recommended for normalization purposes in gene expression studies of liver tissue from patients with chronic hepatitis C or B. Using these genes in combination will ensure very reliable results.

[Housekeeping genes as a reference in quantitative real-time RT-PCR]. / Geny metabolizmu podstawowego jako geny referencyjne w ilosciowym oznaczaniu ekspresji genów metoda real-time PCR.

The determination of gene expression levels in normal tissue is necessary for the analysis and interpretation of results of gene profiling studies in pathological samples. With the real-time reverse transcription-PCR technique, which enables one to detect the amplification rate during the process, assessment of the amount of gene transcript is fast and accurate. The most important problem in this type of analysis is the variability in the amount of genetic material between samples, caused mostly by changes in the efficiency of mRNA isolation and reverse transcription. Therefore, a reference gene to normalize sample variations is required. Quantification of the mRNA of the target and the reference gene in the sample ensures that the changes in transcript levels will influence both genes equally. To be used as a reference, a gene should show stable, unregulated expression in the analyzed sample type. Housekeeping genes (HKGs) fulfill this criterion and they are used for normalization purposes in most expression studies. However, transcript levels of HKGs can vary between different types of tissue (normal and pathological samples) and under different treatment conditions (drugs and chemicals). The aim of this study was to show the differences and the factors which can influence housekeeping gene expressions.

[Molecular basis of hereditary hemochromatosis]. / Molekularne podstawy dziedzicznej hemochromatozy.

Hereditary hemochromatosis (HH) is a genetic metabolic disease characterized by increased intestinal iron absorption and progressive iron loading in the cells of various organs. Human body iron homeostasis involves a number of complicated processes, some of which are not identified yet. Genetic analysis of patients affected by HH recently led to the discovery of many novel proteins and mechanisms that can influence the uptake, transport, storage, and excretion of iron. It also showed that hemochromatosis is a very complex disease and that the type of mutation can influence its clinical manifestation. This review presents the current knowledge about the mechanisms of iron metabolism and describes the types of hereditary hemochromatosis and the mutations which induce the disease.

[Hereditary hemochromatosis: the most frequent inherited human disease]. / Hemochromatoza dziedziczna--najczestsza choroba genetyczna czlowieka.

Hereditary hemochromatosis is now recognized as a very common inherited disease of the Caucasian population. It is defined as a disorder of unique clinicopathology caused by mutations of genes that control iron metabolism. Inappropriately increased intestinal iron absorption and accelerated recycling of iron by macrophages lead to progressive body iron accumulation and the generation of oxidative stress in tissues. This results in significant cellular damage, induction of inflammation, and fibrosis. Liver cirrhosis, hepatocellular carcinoma, diabetes mellitus, and cardiac insufficiency are diagnosed in the advanced phase of this disease. The natural course is modified by environmental factors and personal predisposition. Three forms of hemochromatosis with the pathophysiology of iron overload are described. Among them the classical form, juvenile hemochromatosis with severe course and circulatory insufficiency, and ferroportin disease are presented. Properly directed diagnostics makes early treatment protecting against disease progression and multiorgan insufficiency possible.

HFE gene mutations in Polish patients with disturbances of iron metabolism: an initial assessment.

Hereditary hemochromatosis is one of the most frequent genetic disorders in Europeans, but its prevalence in Poland is still unknown. The aim of the study was an initial assessment of the prevalence of C282Y and H62D HFE gene mutations and their influence on the course of chronic hepatitis C. Forty-one patients were admitted to the Department of Infectious Diseases, Medical University of Gdansk in 2000-2004 because of chronic liver diseases with accompanying disturbances in iron metabolism. Genetic tests for the C282Y and H63D mutations were performed by PCR and restriction fragment length polymorphism (PCR-RFLP) analysis. The HFE gene mutations were confirmed in 24 of 41 (59%) cases with symptoms of chronic liver disease and iron overload, significantly more frequently in HCV-negative patients (12/14 vs. 12/27; chi2=8.28; p=0.05). The C282Y and H63D HFE gene mutations were detected in 16 of 41 (39%) and 9 of 41 (22%) cases, respectively. HCV-negative patients were C282Y carriers significantly more frequently than HCV-positive patients [9/14 vs. 2/27 C282Y homozygotes; 2/14 vs. 3/27 C282Y heterozygotes (p<0.0001)]. The carrier state of the H63D HFE gene mutation was not significantly more frequent in HCV-positive than HCV-negative patients. HCV infection seems to be a negative predictive marker of HFE gene mutations in patients with iron overload. The relationship of H63D HFE gene mutations with chronic hepatitis C and the possible influence of HCV infection on iron metabolism needs further analysis.