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@#Introduction: Chronic Lymphocytic Leukaemia (CLL) is a common type of leukaemia in persons of predominantly European descent but is rare in the Asian population. Disparities in CLL incidence among people of Asian and European descent may be related to the genetic make-up of the two different populations. Hypermethylation event might be one of the silencing mechanisms that inactivate the tumour suppressor genes in CLL. The aim of this study was to determine the hypermethylation status of p16INK4a and p15INK4b among CLL patients and normal individuals. Materials & Methods: A total of 25 CLL patients and 25 normal individuals were recruited for this study and their genomic DNA were extracted from the peripheral blood. The hypermethylation status of p16INK4a and p15INK4b were determined using Methylation Specific-PCR (MS-PCR) whereas DNA sequencing method was applied to selected samples for validation of the MS-PCR results. We also evaluated the association between hypermethylation of these genes with the clinical and demographic characteristics of each group of subjects. Results: Among the CLL patients, p15INK4b partialmethylation occurred in 6 (24%) subjects while methylation occurred in 1 (4%) subject. All the remaining patients were unmethylated at p15INK4b. All the samples showed unmethylation at p16INK4a. Statistically significant associations were found between p15INK4b hypermethylation with the presence of CLL (p=0.01) and with race (p=0.02). Conclusion: Further study using a larger sample size is warranted to explore the significance of DNA methylation incidence among the CLL patients of the Malaysian population. Hence, we suggest that hypermethylation at p15INK4b has a huge influence that kick-starts CLL disease among Malaysians and MS-PCR technique is applicable to be used in methylation study.
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Introduction:Aberrant DNAmethylation patterns in serum DNAmight be used as a biomarker for the early diagnosis and management of cancer patients. The aim of present study was to evaluate DNAmethylation of RASSF1Aand CDH1 in circulating cell free DNA(cfDNA) from serum and paired tissue DNAsamples of breast cancer patients. Material and methods: Methylation-specific PCR was used to assess the methylation status of the two genes in serum and paired tissue sample DNAof 50 breast cancer patients. Biochemical parameters were assessed using an electrochemiluminescence analyzer. Results: Significant correlation found between methylation status of RASSF1A and CDH1 in serum and paired tissue samples of patients. Among clinicopathological findings, CDH1 methylation showed significant association with advance staging and tumor and methylation of RASSF1A exhibited significant association with progesterone receptor and estrogen receptor status in both serum and paired tissue. Vitamins levels were significantly high in cases compared to control group. High folic acid levels were significantly associated with the RASSF1Amethylation. Conclusions: These findings suggest that methylation of cfDNAmay be important in the early detection of breast cancer.
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Background and purpose:Hypermethylated in cancer 1 (HIC1) is silenced in multiple cancer cells and tissues by DNA methylation of epigenetic modification, which may modulate the initiation and progression of tumors. However, there are few reports about this phenomenon in prostate cancer. This study aimed to investigate the status of HIC1 promoter methylation in prostate cancer using methylation methods.Methods:Methylation-specific polymerase chain reaction (MSP) and bisulfate sequencing PCR (BSP) were used to detect the methylation status ofHIC1 promoter in prostate cancer cell lines PC3 and C4-2B, prostate normal cell line PrEC, primary Chinese PCa tissues and the respective healthy control cases.HIC1 expression level was respectively determined by reverse transcription-PCR (RT-PCR) and Western blot assays in PC3, C4-2B and PrEC cells treated with 5-Aza-CdR.Results:We found that the percentages of HIC1 promoter methylation were 78.23%, 72.15% and 10.63% in PC3, C4-2B and PrEC cells by MSP analyses. Moreover, the levels of methylatedHIC1 promoter in 36 primary Chinese PCa tissues compared with the respective healthy control cases were 80.30%vs 31.56%. Expressions ofHIC1 mRNA and protein level were restored in PC3 and C4-2B cells after 5-Aza-CdR treatment.Conclusion:These findings demonstrate thatHIC1 promoter region is hypermethylated in prostate cancer, which results in silence or downregulation ofHIC1. The status ofHIC1 methylation can be a valuable marker in the early stage of prostate cancer and a potential therapeutic target.
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Objective To investigate the relationship between IGF2BP3 hypomethylation with colon tumor differentia?tion. Methods Tissue samples from 41 colorectal cancer were collected from March 2011 to August 2011 in our hospital, among which 19 cases were well-differentiated adenocarcinoma, 12 cases were of moderately differentiated adenocarcinoma and 10 cases were of poorly differentiated adenocarcinoma. Meanwhile biopsy samples from 12 cases of colonic colitis were collected as a control. The expression of IGF2BP3 was assessed by immunohistochemistry and Western blot. An innovate of ELISA technique was used to examine global methylation levels while IGF2BP3 methylation level was tested by methylation specific PCR technique. Results The expressions of IGFBP3 are higher in all colon cancer groups than that in colitis (P<0.05). The expression of IGFBP3 in poorly differentiated adenocarcinoma is higher than that in all the other groups, but there is no significant difference between its expressions in the well differentiated group and in the moderately differentiated adeno?carcinoma group. The global DNA level and IGFBP3 methylation level of every colon cancer group is lower than those in coli?tis (P<0.05). Also, a tendency of decreasing global DNA and IGFBP3 methylation status was observed comparing well differ?entiated towards poorly differentiated carcinomas (P<0.05). Conclusion IGF2BP3 expression in colorectal cancer is asso?ciated with differentiation of colon cancer tissue. A lower global and IGF2BP3 DNA methylation suggest a worse differentia?tion of colon cancer. DNA hypomethylation may therefore play a regulatory role in the expression of IGF2BP3 in colon cancer tissue.
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Objective:This study aims to detect the CpG island methylation status of the ERCC1 gene promoter and the expres-sion of the ERCC1 protein in gastric cancer tissues, as well as to investigate the correlation and significance between ERCC1 gene pro-moter CpG island methylation and protein expression. Methods:Methylation-specific PCR was performed to detect the methylation sta-tus of the ERCC1 gene in tumor tissues and adjacent cancerous tissues from 30 gastric cancer patients. Ten cases of normal gastric tis-sues were used as control. Expression of the ERCC1 protein in gastric cancer tissues, adjacent cancerous tissues, and normal gastric tis-sues was examined by immunohistochemistry S-P method. Results:The methylation rate of the ERCC1 gene promoter CpG island in gastric cancer tissues was significantly higher than that in adjacent cancerous tissues (76.7%vs. 13.3%, P<0.05), and the difference was statistically significant. The incidence of promoter methylation was not found in 10 normal gastric tissues. The negative rate of ERCC1 protein expression in 30 cases of gastric carcinoma tissues was significantly higher than that in adjacent cancerous tissues (70.0% vs. 33.3%, P<0.05), whereas 10 normal gastric tissues all exhibited positive expression for the ERCC1 protein. The tumor tissues with ER-CC1 gene promoter CpG island methylation showed a lower expression of ERCC1 protein than the unmethylated tumor tissues in gas-tric cancer patients. Conclusion:Methylation of the ERCC1 gene promoter CpG island and protein expression are negatively correlat-ed, and methylation of the CpG island of the ERCC1 gene may be one of the main reasons for the down-regulation of protein expres-sion.
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Objective To study the association of ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) promoter region methylation with human esophageal cancer. Methods Promoter region methylation of UCHL1 was dctcctcd by rnethylation specific PCR (MSP) in esophageal cancer cell lines and tissue samples.The expression of UCHL1 was detected by semi-quantitative RT-PCR and Western blot in esophagcal cancer cell lines.5-Aza-2'-deoxycytidine (5-Aza) was applied to reactivate methylated cell lines.ResultsComplete methylation of UCHL1 promoter region was detected in 8 cell lincs (KYSE30,KYSE150,KYSE140,KYSE450,KYSE510,TE3,TE7,TE10).Loss of UCHL1 expression was found in7 cell lines ( KYSE30,KYSE150,KYSE140,KYSE450,KYSE510,TE3,TE7).Reduced expression was found in TE10 cell line. Promoter region hypermethylation was correlated with UCHL1 expression in esophageal cancer cell lines.Re-expression of UCHL1 was induced by 5-Aza treatment in KYSE150 and TE3 cell lines.UCHL1 was frequently methylated in human primary esophageal cancer (74.51％,38/51 ),while no methylation was detected in normal esophageal mucosa (0/10). No association was found between promoter region methylation and age,gender,tumor location,tumor stage or lymph node metastasis.Conclusions UCHL1is silenced by promoter region hypermethylation in human esophageal cancer.Methylation of UCHL1 is frequently happened to primary esophageal cancer and may play an important role in the tumorigenesis.
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PURPOSE: The purpose of the present study was to investigate the aberrance of histone H3 lysine 4 trimethylation (H3K4me3) in patients with IgA Nephropathy (IgAN). MATERIALS AND METHODS: In this study, H3K4me3 variations in peripheral blood mononuclear cells (PBMCs) from 15 IgAN patients and 15 healthy subjects were analyzed using chromatin immunoprecipitation linked to microarrays analysis (ChIP-chip). ChIP real-time PCR was used to validate the microarray results. Expression analysis by quantitative real-time PCR (qRT-PCR) revealed correlations between mRNA and H3K4me3 levels. DNA methylation status was analyzed by quantitative methylation-specific PCR. RESULTS: We found that 321 probes displayed significant H3K4me3 differences in IgAN patients compared with healthy controls. Among these probes, 154 probes displayed increased H3K4me3 and 167 probes demonstrated decreased H3K4me3. For further validation, we selected 4 key relevant genes (FCRL4, GALK2, PTPRN2 and IL1RAPL1) to study. The results of ChIP real-time PCR coincided well with the microarray data. Quantitative RT-PCR revealed the correlations between the mRNA expression and the methylation levels of H3K4me3. Different degrees of DNA methylation alterations appeared on the selected positive genes. CONCLUSION: Our studies indicated that there were significant alterations in H3K4me3 in IgAN patients. These findings may help to explain the disturbed immunity and abnormal glycosylation involved in IgAN patients.
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Adult , Female , Humans , Male , Young Adult , Case-Control Studies , Chromatin Immunoprecipitation , Glomerulonephritis, IGA/genetics , Histones/metabolism , Leukocytes, Mononuclear/metabolism , Lysine/metabolism , Methylation , Oligonucleotide Array Sequence Analysis/methods , Real-Time Polymerase Chain ReactionABSTRACT
To investigate the clinical features, genetic diagnosis, and treatment of a patient with Prader-Willi syndrome(PWS). For a case with clinically suspected PWS, methylation specific PCR(MSPCR)amplification was applied to CpG islands of SNRPN(exon α)gene locus in the 15q11-q13. Furthermore, the diagnosis was comfirmed by the method of bisulfite sequencing PCR(BSPCR). Metabolic status before and after the operation of sleeve gastrectomy were compared. Absence of amplification of paternal allele on chromosome 15q11-q13 was detected in the case by MSPCR, different from the normal control. Results of BSPCR further proved a full methylation of CpG islands in the SNRPN gene locus. Four months after sleeve gastrectomy, systemic metabolic status and ventricular function were improved. MSPCR and BSPCR were both consistent with genetic diagnosis of PWS. Weight loss surgery is expected to be a major therapy of this disease.
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Objective To determine the aberrant methylation status of RASSF1A,p16 and DAPK gene promoter region in induced sputum from lung cancer patients and the value of their combined detection in diagnosing lung cancers. Methods Methylation-specific PCR (MSP) was used to detect the promoter methylation status of RASSF1A,p16, and DAPK genes in induced sputum and pathological tissues from 82 patients with lung cancers and 25 patients with pulmonary benign lesion.We also analyzed the relation between methylation status and clinical pathological data.Results The positive rates of promoter methylation of RASSF1A,p16, and DAPK genes in pathological tissues from patients with lung cancers were 63.4%,59.8%, and 58.5%, respectively,and those in induced sputum were 54.9%,48.8%,and 51.2%, respectively. The promoter methylation of RASSF1A,p16, and DAPK genes were not detected in patients with pulmonary benign lesion.There was a significant difference between the lung cancer group and pulmonary benign lesion group (P＜0.05). The methylation rate of RASSF1A gene was significantly lower in the middle and high differentiation and non-metastastic lymph node of lung cancer tissues than that in the poor differentiation and the metastatic lymph node of lung cancer tissues(P＜0.05), and was not correlated with age, sex, smoking index, clinical stage, and pathological types.The methylation rate of p16, and DAPK genes was not significantly correlated with all the above mentioned factors (P＞0.05). The methylation rate of joint detecting RASSF1A, p16, and DAPK genes was 73.2%. Conclusion Joint detection for promoter hypermethylation of RASSF1A, p16, and DAPK genes in induced sputum may be used as a simple and effective index of the diagnosis and prognose of lung cancers, and can improve the positive rate.
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Objective:To investigate the methylation of CpG island of metallothionein-3 (MT-3) gene in esophageal cancer tissues and normal tissues in middle and south area of Hebei Province and Chaoshan area of Guangdong Province and compared the results with those in low risk area of esophageal cancer. Methods:The blood samples from 10 normal volunteers, 10 embryonic esophageal tissues, 20 esophageal mucosa tissues from normal subjects in low risk area as well as 30 fresh surgical specimens of esophageal cancer and 30 normal marginal tissues in the high risk middle-south Hebei Province and Chaoshan area were collected. Methylation-specific polymerase chain reaction (MSP) was used to detect the methylation status of the CpG island of MT-3 gene in these samples. Its relationship with clinicopatho-logical features was analyzed. Results:There were 20 (33.3%) cases with MT-3 methylation in the marginal tissues of esophageal cancer from high-risk area, which was higher than that in the normal mucosa from low-risk area (P=0.013). And there were 49 (81.7%) cases with MT-3 methylation in esophageal cancer tissues, which was higher than that in normal marginal tissues (P<0.001). But there was no significant difference in the methylation degree between middle-south of Hebei Province and Chaoshan area (P=0.739). Conclusion:MT-3 methylation widely exists in esophageal mucosa and carcinoma tissues. Acquired stimulus may be the main cause of these methylations.
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OBJECTIVE: We analyzed the methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) gene promoter in World Health Organization (WHO) grade III gliomas in association with other molecular markers to evaluate their prevalence. METHODS: The samples of a total of 36 newly WHO grade III glioma patients including 19 anaplastic oligodendrogliomas (AO), 7 anaplastic oligoastrocytomas (AOA), and 10 anaplastic astrocytomas (AA) were analyzed. The methylation status of the MGMT gene promoter was confirmed by methylation-specific polymerase chain reaction. The 1p/19q chromosomal deletion status and EGFR amplification were assessed by Fluorescence In-Situ Hybridization. MGMT, EGFR, EGFRvIII, and p53 expression were analyzed by immunohistochemical staining. RESULTS: The MGMT gene promoter was methylated in 32 (88.9%) and unmethylated in 4 (11.2%). Among them, all of the AO and AOA had methylated MGMT gene promoter without exception. Significant associations between MGMT gene promoter hypermethylation and 1p/19q deletion was observed (p = 0.003). Other molecular markers failed to show significant associations between MGMT gene promoter statuses. CONCLUSION: There was extensive epigenetic silencing of MGMT gene in high grade gliomas with oligodendroglial component. Together with frequent 1p/19q co-deletion in oligodendroglial tumors, this may add plausible explanations supporting the relative favorable prognosis in oligodendroglial tumors compared with pure astrocytic tumors.
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Humans , Astrocytoma , Chimera , DNA , Epigenomics , Fluorescence , Glioma , Methylation , Oligodendroglioma , Polymerase Chain Reaction , Prevalence , Prognosis , ErbB Receptors , Global Health , World Health OrganizationABSTRACT
Objective: To detect the methylation status of human runt-related transcription factor 3 (RUNX 3) gene in bladder cancer tissues and investigate its role in tumorigenesis and progression of bladder caner. Methods: Methylation-specific PCR (MSP) was used to examine the methylation status of RUNX 3 gene in 33 cases of bladder cancer tissues, 8 cases of paired adjacent normal tissues, and 3 cases of normal bladder tissues from non-tumor patients. Results: Aberrant methylation of RUNX 3 was found in 21 out of 33 (63.7%) bladder cancer tissues and 1 out of 8 (12.5%) tumor adjacent normal tissues. There was statistical significance between them (P <0.05). Three normal bladder tissues from non-tumor patients showed no abnormal methylation of RUNX 3. Conclusion: Hypermethylation of RUNX 3 gene in bladder cancer tissues suggests that aberrant methylation of RUNX 3 correlates with tumorigenesis of bladder cancer.
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Loss of E-cadherin (E-cad) expression has been found in multiple cancers and is postulated to facilitate tumor cell dissociation and metastais. Promotor methylation may provides an alternative pathway for loss of gene function. This study evaluated the role of hypermethylation in the down-regulation of E-cad in oral squamous cell carcinoma (OSCC). We examined the E-cad expression by immunohistochemical staining and detected methylation status by methylation-specific polymerase chain reaction (MSP) in 20 OSCC tissues. Overally, 12 (60 %) cases of hypermethylation of E-cad were detected and we found there were no correlation between methylation and age, histologic grade, lympn node metastasis, tumor size and clinical stage. However, Eleven (73.3 %) of 15 samples which was negative for E-cad staining showed hypermethylation of E-cad promotor region. On the other hand, only one (20 %) of 5 E-cad positive sample was observed with methylated status. The underexpression of E-cad was found to be related to promotor hypermethylation (p=0.035). In conclusion, we suggest that hypermethylation play a role in inactivation of E-cad gene and may be a appreciable biomarker for diagnosis and treatment of OSCC.
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Cadherins , Carcinoma, Squamous Cell , Dissociative Disorders , Down-Regulation , Hand , Methylation , Neoplasm Metastasis , Polymerase Chain Reaction , Promoter Regions, GeneticABSTRACT
Loss of E-cadherin (E-cad) expression has been found in multiple cancers and is postulated to facilitate tumor cell dissociation and metastais. Promotor methylation may provides an alternative pathway for loss of gene function. This study evaluated the role of hypermethylation in the down-regulation of E-cad in oral squamous cell carcinoma (OSCC). We examined the E-cad expression by immunohistochemical staining and detected methylation status by methylation-specific polymerase chain reaction (MSP) in 20 OSCC tissues. Overally, 12 (60 %) cases of hypermethylation of E-cad were detected and we found there were no correlation between methylation and age, histologic grade, lympn node metastasis, tumor size and clinical stage. However, Eleven (73.3 %) of 15 samples which was negative for E-cad staining showed hypermethylation of E-cad promotor region. On the other hand, only one (20 %) of 5 E-cad positive sample was observed with methylated status. The underexpression of E-cad was found to be related to promotor hypermethylation (p=0.035). In conclusion, we suggest that hypermethylation play a role in inactivation of E-cad gene and may be a appreciable biomarker for diagnosis and treatment of OSCC.
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Cadherins , Carcinoma, Squamous Cell , Dissociative Disorders , Down-Regulation , Hand , Methylation , Neoplasm Metastasis , Polymerase Chain Reaction , Promoter Regions, GeneticABSTRACT
Transitional-CpG methylation between unmethylated promoters and nearby methylated retroelements plays a role in the establishment of tissue-specific transcription. This study examined whether chromosomal losses reducing the active genes in cancers can change transitional-CpG methylation and the transcription activity in a cancer-type-dependent manner. The transitional-CpG sites at the CpG-island margins of nine genes and the non-island-CpG sites round the transcription start sites of six genes lacking CpG islands were examined by methylation-specific polymerase chain reaction (PCR) analysis. The number of active genes in normal and cancerous tissues of the stomach, colon, breast, and nasopharynx were analyzed using the public data in silico. The CpG-island margins and non-island CpG sites tended to be hypermethylated and hypomethylated in all cancer types, respectively. The CpG-island margins were hypermethylated and a low number of genes were active in the normal stomach compared with other normal tissues. In gastric cancers, the CpG-island margins and non-island-CpG sites were hypomethylated in association with high-level chromosomal losses, and the number of active genes increased. Colon, breast, and nasopharyngeal cancers showed no significant association between the chromosomal losses and methylation changes. These findings suggest that chromosomal losses in gastric cancers are associated with the hypomethylation of the gene-control regions and the increased number of active genes.
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Humans , Alu Elements/genetics , Chromosome Deletion , CpG Islands/genetics , DNA Methylation , DNA, Neoplasm/chemistry , Gene Expression Profiling , Genes, Neoplasm , Long Interspersed Nucleotide Elements/genetics , Polymerase Chain Reaction , Promoter Regions, Genetic , Stomach Neoplasms/geneticsABSTRACT
Objective To investigate the relationship between promoter methylation of RASSF1A gene and laryngeal squamous cell carcinoma.Methods A methylation-specific PCR was performed to detect the promoter methylation of RASSF1A gene in 48 tumor tissues,48 corresponding normal tissues and 48 normal blood plasma.The expression of RASSF1A protein was determined by means of Western blotting.Results The methylation in RASSF1A gene was detected in 34(70.83%) tumor tissue samples,11(22.92%) corresponding normal tissue samples and 6(12.50%) blood plasma samples,respectively.The methylation degree of tumor tissue was higher than that of corresponding normal tissues and normal blood plasma(P
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Background and purpose:To explore the possibility of genetic re-expression silenced by DNA aberrant hypermethylation which is a common epigenetic modification in carcinogenesis. 5-Aza-CdR, an inhibitor of DNA methylation, was used to determine the effects of expression of tumor suppressor gene E-cadherin in tumor cell lines. Methods:Methylation specific PCR(MSP) was utilized to examine methylation status of E-cad gene on breast carcinoma cell line MDA-MB-435 before and after the treatment with 5-Aza-CdR. Immunohistochemistry(IHC) was used to test the expression of E-cad protein. Semi-quantitative RT-PCR method was used to detect the changes of E-cad mRNA.Results:1).E-cad methylation was positive(116bp) and unmethylation was negative on MDA-MB-435 cell before the treatment with 5-Aza-CdR. After being treated with 5.0umol/L 5-Aza-CdR for 3 days, methylation turned negative and unmethylation positive bands(97bp) were detected. 2).The E-cad protein expression was not detected by immunohistochemistry on MDA-MB-435 cell before the treatment, while E-cad staining was positive on the cell membrane after the treatment. 3). The E-cad mRNA failed to be amplified in cells before the treatment. After incubation at variable concentrations of 0.5 ?mol/L, 1.0 ?mol/L, 2.0 ?mol/L and 5.0 ?mol/L 5-Aza-CdR for 3 days, respectively, E-cad mRNA expression was detected on the fourth day in a dose-dependent manner. Correlation between the mRNA expression level and the agent concentration was observed.Conclusions:The demethylation agent 5-Aza-CdR can reverse the aberrant E-cad methylation status in MDA-MB-435 and re-expressed E-cad mRNA and protein.
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Objective To investigate the relationship between the characteristics of promoter methylation of thyroid stimulating hormone receptor(TSHR) gene in papillary thyroid Carcinomas(PTC) and the clinical manifestation of PTC. Methods The methylation status of TSHR gene was detected by methylation specific PCR technique(MSP).Results (1) The methylation rate of TSHR gene in PTC tissues was 64.7%(22/34),while the methylation rate of TSHR gene in adjacent thyroid tissues(ATT) was 26.5%(9/34),and the rate of methylation of TSHR promoter in PTC was significantly higher than of ATT(P
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The relationship between hypermethylation of CpG islands in the promoter regions of O6methylguanine DNA methyltransferase (MGMT)genes and laryngeal squamous cell carcinoma was explored. Methylation-specific PCR and semi-quantitative RT-PCR were used to study the promoter methylation and mRNA expression of the MGMT gene in laryngeal carcinoma tissues, t issues adjacent to the tumor and normal laryngeal tissues. Hypermethylation of MGMT gene was detected in 16 samples of 46 (34.8 %) laryngeal squamous cell carcinoma samples. However, the MGMT hypermethylation was not detected in all tissues adjacent to the tumors and normal tissues. No significant difference in MGMT gene hypermethylation was found in samples with different histological grades (x2= 3. 130, P=0. 077) or in samples from patients with different TNM status (x2=3. 957, P=0. 138). No expression of MGMT mRNA was detected in all hypermethylated laryngeal carcinoma tissues. The expression of MGMT mRNA was detected in all unmethylated laryngeal carcinoma tissues, tissues adjacent to the tumors and normal tissues. It suggests that MGMT gene promoter hypermethylation is associated with MGMT gene transcription loss in laryngeal carcinoma tissues and possibly plays an important role in carcinogenesis of laryngeal tissues.
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Objective To search and analyze the DNA methylation-related genes of ?-thalassemia by oligonucleotide microarray in order to explore a new method for early diagnosis of ?-thalassemia.Methods The cord blood samples of 2 children with ?-thalassemia and 2 health children were detected by a chip containing human DNA methylation 30 178 oligonucleotide probes.The chip results were verified by the methods of methylation-specific PCR (MSP) and real-time PCR.The statistical significance of differentially expressed genes was found on non-supervised clustering (Hierarchical clustering).Results A total of 209 genetic differences (ratio≥2.0 or≤0.5) were showed by 2 groups of chips,and of them 113 genes were up-regulated and 96 genes were down-regulated.The results showed that the methylation-related gene erythroblastic leukemia viral (v-erb-a) was of hypermethylation compared with the normal blood.Conclusion A large number of differentially expressed genes are screened out by the technology of High-throughput DNA methylation of the gene chip in thalassemia.The DNA methylation-related gene of v-erb-a is of hypermethylation in thalassemia.Our methods offers a new idea and approach for prenatal diagnosis for thalassemia by the DNA methylation-related microarray.