Ignite Creation Date:
2024-05-06 @ 7:15 AM
Last Modification Date:
2024-10-26 @ 11:46 AM
Study NCT ID:
NCT02491567
Status:
COMPLETED
Last Update Posted:
2019-09-26
First Post:
2014-12-23
Brief Title:
DNA Methylation and Autoimmune Thyroid Diseases
Sponsor:
Aristotle University Of Thessaloniki
Organization:
Aristotle University Of Thessaloniki
Study Overview
Official Title:
Study of DNA Methylation in Children and Adolescents With Autoimmune Thyroid Diseases
Status:
COMPLETED
Status Verified Date:
2019-09
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
THYRODNA
Brief Summary:
Hashimoto Thyroiditis HT and Graves Disease GD are known to be caused by abnormal immune response against self cells and tissues Epigenetics is a novel field of biology studying the mechanisms by which the environment interacts with the genotype to produce a variety of phenotypes through modifications to chromatin that do not directly alter the DNA sequence A very limited number of epigenetic studies have been published in patients with HT and GD so far Therefore the purpose of this study is to analyze DNA methylation status in White Blood Cells WBCs within the promoter regions of genomic sites that have been previously identified as susceptibility loci or sites for autoimmune thyroid disease such as the CD40L FOXP3 CTLA4 PTPN22 IL2RA FCRL3 and HLADRB1 genes
Detailed Description:
Hashimoto Thyroiditis HT and Graves Disease GD are known to be caused by abnormal immune response against self cells and tissues HT involves a cell-mediated autoimmune destruction of the thyroid leading to hypothyroidism GD is caused by a process in which immune cells make stimulating antibodies against the thyroid stimulating hormone TSH receptor on the thyroid gland thus leading to hyperthyroidism Although there is substantial evidence that genetic factors increase the risk for developing autoimmune diseases monozygotic twins still remain discordant for disease disease concordance is never 100 thus suggesting a role for environmental factors and epigenetics
Epigenetics is a novel field of biology studying the mechanisms by which the environment interacts with the genotype to produce a variety of phenotypes through modifications to chromatin that do not directly alter the DNA sequence These modifications have been associated with altered gene expression and silencing of repetitive elements and can be inherited mitotically Epigenetic mechanisms include DNA methylation histone modifications or miRNA post-transcriptional regulation DNA methylation involves the covalent addition of a methyl group to the carbon-5 position in the CpG dinucleotide from the methyl donor S-adenosylmethionine and is mediated by a group of enzymes called DNA methyltransferases DNMTs CpG dinucleotides are typically grouped together in regions known as CGIs islands CGIs can be found in the promoter regions of genes and CpG methylation of these gene promoters is associated with transcriptional silencing In contrast hypermethylated genes have been found to be transcriptionally active
A very limited number of epigenetic studies have been published in patients with HT and GD so far Therefore the purpose of this study is to analyze DNA methylation status in White Blood Cells WBCs within the promoter regions of genomic sites that have been previously identified as susceptibility loci or sites for autoimmune thyroid disease such as the CD40L FOXP3 CTLA4 PTPN22 IL2RA FCRL3 and HLADRB1 genes
Initially recruitment of patients and controls as well as blood sample collection will be done A complete physical examination will also be performed in all participants included in the study and a detailed personal family gestational and perinatal history will be obtained as well before inclusion Blood samples by all participants will be collected and centrifuged and then White Blood Cells WBCs plasma and serum will be separated and stored in a deep freezer
Laboratory analyses will follow DNA will be isolated from peripheral leukocytes using the QIAamp DNA Blood Mini Kit according to the manufacturers instructions It will then be treated with sodium bisulfite using the Zymo EZ DNA Methylation-Gold Kit again according to the manufacturers protocol Therefore unmethylated cytosines will be converted into uracyls whereas methylated cytosines will remain unchanged Quantification of the methylation status of DNA at the gene promoter regions under study will be made using specific primers that detect modified DNA by real-time PCR and analysis of the melting curves of the selected fragments of DNA Amplicons will also be analyzed by electrophoresis and visualized by ultraviolet trans-illumination
An electronic Data Base will be constructed and Statistical Analysis will follow Results and Conclusions will be published in peer-review journals and presented in International Meetings
Epigenetics is a novel field of biology studying the mechanisms by which the environment interacts with the genotype to produce a variety of phenotypes through modifications to chromatin that do not directly alter the DNA sequence These modifications have been associated with altered gene expression and silencing of repetitive elements and can be inherited mitotically Epigenetic mechanisms include DNA methylation histone modifications or miRNA post-transcriptional regulation DNA methylation involves the covalent addition of a methyl group to the carbon-5 position in the CpG dinucleotide from the methyl donor S-adenosylmethionine and is mediated by a group of enzymes called DNA methyltransferases DNMTs CpG dinucleotides are typically grouped together in regions known as CGIs islands CGIs can be found in the promoter regions of genes and CpG methylation of these gene promoters is associated with transcriptional silencing In contrast hypermethylated genes have been found to be transcriptionally active
A very limited number of epigenetic studies have been published in patients with HT and GD so far Therefore the purpose of this study is to analyze DNA methylation status in White Blood Cells WBCs within the promoter regions of genomic sites that have been previously identified as susceptibility loci or sites for autoimmune thyroid disease such as the CD40L FOXP3 CTLA4 PTPN22 IL2RA FCRL3 and HLADRB1 genes
Initially recruitment of patients and controls as well as blood sample collection will be done A complete physical examination will also be performed in all participants included in the study and a detailed personal family gestational and perinatal history will be obtained as well before inclusion Blood samples by all participants will be collected and centrifuged and then White Blood Cells WBCs plasma and serum will be separated and stored in a deep freezer
Laboratory analyses will follow DNA will be isolated from peripheral leukocytes using the QIAamp DNA Blood Mini Kit according to the manufacturers instructions It will then be treated with sodium bisulfite using the Zymo EZ DNA Methylation-Gold Kit again according to the manufacturers protocol Therefore unmethylated cytosines will be converted into uracyls whereas methylated cytosines will remain unchanged Quantification of the methylation status of DNA at the gene promoter regions under study will be made using specific primers that detect modified DNA by real-time PCR and analysis of the melting curves of the selected fragments of DNA Amplicons will also be analyzed by electrophoresis and visualized by ultraviolet trans-illumination
An electronic Data Base will be constructed and Statistical Analysis will follow Results and Conclusions will be published in peer-review journals and presented in International Meetings
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None