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Volume Two
In This Issue:
Cancer and DNA Methylation
Introduction
Colorectal Cancer Tumorigenesis
DNA Methylation
Detecting DNA Methylation
Clinical Relevance of DNA Methylation
DNA Methylation Biomarkers
Biomarker Discovery and Development
Detecting Cancer In Blood.
Cancer and DNA Methylation
Introduction1
Cancer is increasingly defined and accepted as both a genetic and
epigenetic disease. Epigenetics can be best described as a stable,
heritable alteration in gene expression potential that occurs during cell
development and proliferation and is not mediated by genetic changes
in the DNA sequence. When individual genes or DNA become altered,
a complex array of epigenetic regulatory mechanisms that control
gene expression in both normal and cancerous cells are affected. These
detectable changes become valuable indicators and biomarkers for early
cancer detection.
DNA METHYLATION IS ONE OF THE MOST COMMONLY OCCURRING
EPIGENETIC EVENTS IN HUMANS — THEREFORE, MEASUREABLE LEVELS OF
DNA METHYLATION PROVIDES IMPACTFUL DIAGNOSTIC INFORMATION
FOR CLINICIANS.1
Aberrant DNA methylation is an example of an important epigenetic
event that occurs in human cancers, and when assessed, can provide
critical diagnostic and prognostic information important for clinical
decision making. Aberrant DNA methylation is the most extensively
studied epigenetic mechanism in cancer, and because it occurs very
early in the progression to adenocarcinoma, it has become a valuable
tool for early cancer detection. As an example, SEPT9 (Septin 9) DNA
methylation and the changes in the activity and expression of SEPT9 gene
have been associated with various cancers (Figure 1). Epi proColon® is a
test based on the detection of methylated Septin 9 DNA in blood which
is associated with colorectal cancer.
FIGURE 1: Commonly methylated and silenced genes in CRC
Specific genes and loci become aberrantly methylated in
the sequence to adenocarcinoma; these staged alterations
contribute to both the initiation and progression of cancers.
APCMINT1*
CDH1 MINT31*
CDH13 MLH1
CDKN2A/p16RASSF1A
CRABPRUNx3
CXCL12
SEPT9
DAPKSFRP1
ESR1SFRP2
HLTFSLC5A8
ID4TIMP3
IRF8THBS1/ TSP1
MGMTVIM
Lao, VV. Epigenetics and Colorectal Cancer. Nat Rev Gastroenterol Hepatol,
2011.*Loci found to be methylated in tumor; not genes.
Colorectal Cancer Tumorigenesis
The process by which normal epithelial cells transform to cancer
cells requires the reprogramming of multiple critical biological and
regulatory pathways. On this basis, colorectal cancer is considered
a genetic and epigenetic disease arising from DNA mutations
and/ or epigenetic changes in epithelial cells. These neoplastic
changes disrupt gene function within the cells and as a result,
tightly regulated and critical cell processes are reprogrammed,
transforming normal cells into cancer cells. Cell growth becomes
uncontrolled and limitless, and through a distinct series of biological
and metabolic pathways,the cells proliferate and invade adjacent
and distant tissues, resulting in metastasis.2 Tumor cells
that penetrate the basement membrane to invade the underlying
tissues are a key feature of malignancy (Figure 2).2
While there are a subset of well-characterized heritable causes
of CRC such as familial adenomatous polyposis (FAP), hereditary
non-polyposis colorectal cancer (HPNCC) or Lynch syndrome,
the majority of CRCs are sporadically-occurring cancers.3 Several
decades of epigenetic research have associated aberrant
DNA methylation occurring in the early events leading to the
malignant progression in sporadic CRC.1,4
FIGURE 2: Model for the progression from normal gut epithelium to adenocarcinoma.
Normal Epithelium
Abberant Crypt Focus (ACF)
APC Failure
2
Early Adenoma
Late Adenoma/Polyp
K-Ras Mutation
Adenocarcinoma
p53 Mutation/Loss
DNA Methylation5–12
FIGURE 3: Cytosine methylation
In humans, DNA methylation is a natural phenomenon that plays
a critical regulatory role in gene transcription, embryonic cell
development, in somatic cells, and is transmitted to daughter cells
with high fidelity. DNA methylation is a chemical modification in
which the cytosine base is altered through an enzymatic process
by DNA methyltransferase (DNMT) to produce 5-methylcytosine
(Figure 3).
5-methylcytosine
Cytosine
CH3
H
C5
H
C
NH2
C5
H
C
methyl group
C
NH2
C
DNMTs
DNA methylation occurs at the C-5 position of cytosine nucleotides
N
N
N
N
H
H
that exist in a cytosine-guanine (CpG) sequence context. The
C
C
distribution of CpG sequences in the genome is non-random.
O
O
Regions of increased CpG density, called CpG islands, frequently are
found in the promoter regions of genes. The methylation status of
the CpG islands often correlates with the level of gene expression
such that DNA methylation provides an epigenetic mechanism for regulation of gene expression. The majority of CpG cytosines are
methylated in normal human cells—the unmethylated CpGs primarily occur in CpG islands that are often associated with gene promoters.
Alterations in DNA methylation contribute to CRC heterogeneity and can be identified by their unique methylated gene signatures.
Molecular sub-types include microsatellite instability (MSI), chromosomal instability (CIN) and CPG island methylator phenotype (CIMP).
Aberrant DNA methylation is associated with cancer in two forms, hypomethylation and hypermethylation, the latter occurring at CpG
islands in the promoter regions of genes and is associated with gene silencing. Global hypomethylation plays a role in genetic instability
in both the development and progression of cancer.
Analysis of DNA methylation in tumors revealed changes in the majority of cases tested. For example, Septin 9 hypermethylation occurs
in the majority of CRC adenoma and tumor tissues tested. Concurrent hypermethylation changes in many CpG islands are associated
with a distinct subset of colorectal cancer that accounts for approximately 20% of CRC, and is known as the CpG islands methylator
phenotype (CIMP).
Detecting DNA Methylation
While a number of technologies have been
developed to discriminate sequences based
on methylation status, the bisulfite treatment
approach is the current state of the art for
the sensitivity and throughput requirements
of the molecular diagnostics industry. As
illustrated in Figure 4, when treated with a
high concentration of bisulfite, unmethylated
cytosines are converted to uracil while
methylated cytosine residues are resistant
to conversion. As a consequence, the DNA
sequence is altered based on the methylation
status. This results in a sequence difference that
can be analyzed by standard molecular methods
such as hybridization or PCR amplification.
FIGURE 4: Bisulfite treatment for the detection of DNA methylation
Unmethylated DNA
Methylated DNA (cytosine)
5'
A
C
C
G
T
3'
Untreated
DNA
5'
A
C
C
G
T
3'
5'
A
U
U
G
T
3'
Bisulfite
Treatment
5'
A
U
C
G
T
3'
5'
A
T
T
G
T
3'
5'
A
T
C
G
T
3'
T
A
A
C
A
5'
3'
T
A
G
C
A
5'
3'
First PCR
Cycle
Treatment of DNA with bisulfite converts unmethylated cytosine residues to uracil; methylated
cytosine (5-methylcytosine) residues remain unchanged; bisulfite-modified DNA is analyzed by RealTime PCR where converted cytosine-uracil residues will be detected as thymine, and unconverted
5-methylcytosine residues, as cystosines.
To achieve the high sensitivity for detection of
methylated tumor DNA circulating in blood,
bisulfite-modified DNA is analyzed by Real-Time PCR (MethylLight™). The Epigenomics’ HeavyMethyl® core technology combines the
use of primers that amplify the target biomarker regardless of methylation status, with a blocking oligo that suppresses the amplification
of unmethylated DNA, and a methylation-specific probe to detect the amplified methylated sequence (Figure 5). The proprietary
HeavyMethyl core technology enables detection of exceptionally low copy number tumor DNA in a background of non-tumor DNA in
plasma.13
3
FIGURE 5: HeavyMethyl® Real-Time PCR
MethylLight® Probe
Blocker
er
Prim
Unmethylated Target DNA
Primer
MethylLight Probe
®
ker
Bloc
Methylated Target DNA
Primer
Primer
Unmethylated
CpGs
Methylated
CpGs
A. In the unmethylated case, the blocker oligonucleotide prevents amplification of the target and the MethyLight methylation
specific probe does not bind.
B. In the methylated case, the blocker does not bind, amplification proceeds, the MethyLight probe binds the
methylated target sequence and produces fluorescence when hydrolyzed during amplification.
Clinical Relevance of DNA Methylation
Recent evidence points to the widespread relevance of DNA methylation in a host of human diseases and co-morbid conditions, including
psychotic disorders, obesity, diabetes, and multiple sclerosis, among others. In the nearly 20 years that DNA methylation changes
associated with carcinogenesis were first described, more than 10 distinct DNA methylation tests with clinical applications in oncology
have appeared. A similar trajectory can be predicted over the next 10 to 15 years for the many human diseases in which DNA methylation
is now being implicated as an etiologic, prognostic and predictive marker. Recent publications citing the clinical utility for methylated
Septin 9 (FDA-approved Epi proColon®) as well as other relevant publications on this topic are located below References at the end of
this newsletter.
THERE IS A NEED FOR A PREVENTIVE STRATEGY THAT CAN UTILIZE BIOMARKERS IN ORDER TO STRATIFY PATIENTS INTO APPROPRIATE
SCREENING AND SURVEILLANCE PROGRAMS.3
DNA Methylation Biomarkers
Since the late 1990’s, there have been thousands of publications associating aberrant DNA methylation with disease, particularly in the
field of oncology. Given the essential role that DNA methylation appears to play in cancer biology, it is not surprising that DNA methylation
profiling is yielding a treasure trove of biomarkers with broad applications in cancer diagnostics and therapeutic management. Because
aberrant changes in DNA methylation are often early events in carcinogenesis, and are present in some precancerous lesions, these
biomarkers are able to play significant roles in early detection and tumor confirmation. And, for tumors that are already diagnosed, a
range of diagnostic, prognostic, and predictive DNA methylation biomarkers can be used for analysis to help the clinician intervene and
manage the course of treatment. A few examples of DNA methylation biomarkers are shown in Table 1.
4
TABLE 1: Methylated DNA Biomarkers (examples)
Biomarker
Application
Cancer
Tissue
Commercial Test
Company
SEPT9
Early Detection
Colorectal
Blood
Epi proColon®
Epi proColon® 2.0 CE
SensiColon mS9 Colorectal Cancer
Epigenomics Inc.
Epigenomics AG*
BioChain*
Abbott Molecular*
MLH-1
Early Detection
Lynch/Hereditary
Colon or endometrial
Nonpolyposis
tumors
Colorectal Cancer
(HNPCC) Screen
MLH-1 Hypermethylation Analysis
Lab-Developed Tests
(LDTs)
SHOX2, PTGER4
Confirmation
Lung
Bronchial fluid-blood
Epi proLung®Epigenomics*
MGMT
Predictive
Brain
Tumor
PredictMDx™ Brain Cancer
MDxHealth
GST-PI ConfirmationProstate
Tissue
PredictMDx™
MDxHealth
*Only available outside the US
Biomarker Discovery and Development
The biomarker discovery team at Epigenomics used genome-wide discovery methods to identify and characterize hundreds of DNA
methylation-based biomarkers that could discriminate colorectal cancer tumor DNA from DNA extracted from normal epithelia.
Biomarkers were analyzed using a Receiver Operator Curve (ROC) approach comparing tumor with normal colon epithelia, then tumor
with other tissues, and ranked based on Area Under the Curve (AUC). The selected markers were then filtered for negativity with peripheral
blood leukocyte DNA as a surrogate for plasma DNA. Based on these criteria, the Company developed sensitive Real-Time PCR assays
and tested 10 markers using patient plasma samples. In multiple independent sample sets tested, the detection of hypermethylation in a
promoter region of the SEPT9 gene showed the best discrimination for the detection of colorectal cancer.
SEPTINS ARE A FAMILY OF CONSERVED, MULTIFUNCTIONAL PROTEINS THAT ARE INVOLVED IN CRITICAL CELLULAR PROCESSES AND
REGULATION INCLUDING CELL DIVISION. THE SEPT9 GENE CODES FOR ~15 ISOFORMS OF THE SEPT9 PROTEIN. THE VARIOUS SEPT9 ISOFORMS
INTERACT WITH OTHER SEPTINS TO PERFORM THEIR SPECIFIC FUNCTIONS.14
The Septin 9 biomarker is based on the
methylation status of a specific DNA sequence
in the promoter region of the SEPT9_v2
transcript. The Septin gene family, of which
SEPT9 is a member, comprises at least
13 genes that encode conserved GTPase
binding cytoskeleton-related proteins that are
associated with tumorigenesis.15 The SEPT9
gene is complex with multiple promoters
and splice variants (Figure 6). As illustrated,
the methylated Septin 9 biomarker maps
to the gamma promoter region that is
associated with the v2 transcript. The area of
hypermethylation was localized to the gamma
promoter by sequence analysis of CpG islands
in adjacent promoters. The methylation status
of these other regions is not correlated with
colorectal cancer status.
Proteins in the Septin family have roles
in cytokinesis, vesicle trafficking, polarity
determination, forming membrane diffusion
barriers, as well as in microtubule and actin
dynamics.
FIGURE 6: SEPT9 Transcript Maps
*
SEPT9_v1
1e2
3
Septin 9
4567891011
12
*
SEPT9_v2
1γ
3
4567891011
12
*
SEPT9_v3
1a
3
4567891011
12
*
SEPT9_v4
1β
3
4567891011
12
*
SEPT9_v4*
1ζ2
3
4567891011
12
*
SEPT9_v5
* Stop Codon
1δ
4567891011
Exons
Untranslated regions
AUG**
12
Septin 9 Biomarker overlaps AUG
Exons
Transcript maps for multiple SEPT9 splice variants. The methylated Septin 9 biomarker maps to the
promoter region of SEPT9_v2 as shown in line two.15
**
Translational start codon
5
The proteins can form hetero-oligomeric complexes and possibly
function as dynamic protein scaffolds.16 The potential role of
Septins in cancer was first suggested in the late 1990’s with
the observation that MLL:Septin gene fusions, including SEPT9,
occurred in hematological malignancies.17 Additional evidence
linking SEPT9 and malignancy includes the observation that the
SEPT9 locus is a common integration site for the SL–3 retrovirus
in T-cell lymphomas, and the SEPT9 locus, located at 17q25.3,
was identified as a common site for allelic imbalance in sporadic
ovarian and breast cancer (Figure 7).15,16
To date, the specific role of SEPT9 has not been illucidated.
Considering the complexity of this locus, the associated and
apparently contradictory activities of tumor suppression15 and
epithelial to mesenchymal transition18 are not surprising. Although
the specific function of the Septin 9 biomarker splice variant
(SEPT9_v2) is not known, hypermethylation of this sequence is
clearly associated with malignant transformation in colorectal
cancer and studies are ongoing to clarify its function.19
FIGURE 5: Methylated SEPT9 gene location
14,21
17p13.2
17p12
17p11.1
17q11.1
17q12
17q21.2
17q21.32
17q22
17q23.2
17q24.1
The SEPT9 gene is located from bp
In parallel with the discovery and development of colorectal
17q24.3
75,277,491 to bp 75,496,677 on
cancer biomarkers, the Company focused development efforts
chromosome 17. Chromosome 17 spans ~
17q25.2
on technology to isolate and analyze the cell-free DNA (cfDNA)
79 million base pairs and likely contains
between 1,200 and 1,500 genes.
fraction in peripheral blood. Reports of free DNA in plasma were
17q25.3
SEPT9
made in the 1940’s and DNA levels were associated with diseases
such as Systemic Lupus Erythematosus in the 1960’s.20 Through
the 1970’s and 1980’s, publications associating cfDNA levels and cancer began to appear. With the development of more sensitive
amplification-based technology, specific mutations confirmed the tumor origin of target sequences in serum and plasma, and DNA
methylation changes associated with cancer were reported in the 1990’s.20 As part of the Company’s development strategy, Epigenomics’
DNA extraction technology was optimized to capture cfDNA from plasma along with bisulfite chemistry to analyze DNA methylation in
this specific sample type. Real-Time PCR assays having very high sensitivity were developed to detect low copy methylated biomarkers.
Following the discovery of differentially methylated biomarkers such as Septin 9 in tumor tissue samples, the Company demonstrated
and confirmed the ability to detect and measure these biomarkers in plasma thus providing the foundation for further diagnostic product
development. On this basis, Epigenomics moved forward with the development of a plasma-based, Real-Time PCR test for the detection
of methylated Septin 9 DNA. Epi proColon®, evaluated in three randomized multicenter clinical trials, was FDA-approved April 2016 for
CRC screening for eligible people who are unwilling or unable to be screened by recommended methods.
THE ROLE OF DNA METHYLATION AS CLINICAL BIOMARKERS IS ONLY BEGINNING TO EMERGE. IT IS NOW WELL ESTABLISHED THAT EPIGENETIC
EVENTS ARE DRIVERS OF CRC TUMORIGENESIS, WITH MORE GENES IN THE CRC GENOME ALTERED BY DNA METHYLATION THAN BY GENE
MUTATIONS. GIVEN THAT THESE ALTERATIONS PRODUCE UNIQUE AND IDENTIFIABLE METHYLATED GENE SIGNATURES, THE PROMISE OF
CLINICAL UTILITY IS SIGNIFICANT FOR DNA METHYLATION AS CLINICAL BIOMARKERS FOR DIAGNOSIS, PROGNOSIS AND THERAPEUTIC
MANAGEMENT OF COLORECTAL CANCER.11
6
Simple Overview: CRC Tumorigenesis and Methylated Septin 9 DNA Biomarker
METHYLATION OF DNA
A epigenetic alteration that adds a methyl group to the 5’ position of cytosine, altering expression/activity
Expression or Activity
is altered / silenced
Gene Inactive
Gene Active
EPIGENETIC ALTERATION
An early event on tumorigenesis
Normal colon cells undergo
transformation to tumor cells
CRC Tumor Cells
Normal Cells
METHYLATION OF SEPT9 GENE
Septin 9 is a GTP-binding protein with critical functionality. Cytosine residues become methylated in CRC tissues.
Septin 9
SEPT 9_v2
1γ
3
4567891011
12
BLOOD-BASED DNA TUMOR BIOMARKER
Methylated Septin 9 cell-free DNA
is shed into the bloodstream
by CRC tumor cells
Cell-Free Septin 9 DNA in Plasma
CRC Tumor Tissue
METHYLATED SEPTIN 9 DNA BIOMARKER FOR CRC
Detectable in plasma by Real-Time PCR
Septin 9
Plasma
DNA Extraction
Bisulfite Conversion
& Purification
Duplex RT-PCR
Data Analysis
7
REFERENCES
1 Mikeska T et. al. DNA methylation biomarkers in cancer: progress towards clinical
implementation. Expert Rev Mol Diagn. 2012, 12(5):473–487.
2 Colon Cancer Treatment, Staging, and Prognosis. National Cancer Institute (NCI),
2012.
3 Migliore L et. al. Genetics, cytogenetics, and epigenetics of colorectal cancer.
J Biomed and Biotech. 2011, Article ID 792362, 19 pages.
4 Paska A et. al. Aberrant methylation patterns in cancer: a clinical view. Biochemia
Medica. 2015, 25(2):161-76.
5 Laird P et. al. DNA methylation and cancer. Human Molecular Genetics. 1994,
3:1487–1495.
6 Baylin S et. al. A decade of exploring the cancer epigenome-biological and
translational implications. Nat Rev Cancer. 2011, 11(10):726–4.
7 Gama-Sosa M et. al. The 5-methylcytosine content of DNA from human tumors.
Nucleic Acids Res. 1983,11:6883–6894.
8 Feinberg A et. al. Hypomethylation distinguishes genes of some human cancers
from their normal counterparts. Nature. 1983, (301):89–92.
9 Erlich M et. al. DNA hypomethylation in cancer cells. Epigenomics. 2009, 1(2):239–
259.
10 Markowitz S et. al. Molecular origins of cancer: molecular basis of colorectal cancer.
N Engl J Med. 2009, 361(25):2449–2460.
11 Lao V et. al. Epigenetics and colorectal cancer. Nat Rev Gastroenterol Hepatol.
2011, 8(12):686–700.
12 Lofton-Day C et. al. DNA methylation biomarkers for blood-based colorectal cancer
screening. 2008. Clin Chem, 54(2):414–423.
13 Epigenomics data on file.
14 Genetics Home Reference, U.S. Library of Medicine, 2012, Ver July, 2012.
15 Connolly D et. al. Septin roles in tumorigenesis. 2011. Biol Chem, 392(8–9):725–
738.
16 Russell H et. al. Do Septins have a role in cancer? Brit J Cancer. 2005, 93:499–
503.Cottrell S et. al. 2004. A real-time PCR assay for DNA-methylation using
methylation-specific blockers. 2005. NAR 32, No. 1 e10.
17 Cerveira N et. al. MLL-SEPTIN gene fusions in hematological malignancies. Biol
Chem. 2011, Vol 392:713–724.
18 Shankar J et. al. Pseudopodial Actin Dynamics Control Epithelial-Mesenchymal
Transition in Metastatic Cancer Cells. 2010, Can Res 70(9):3780–3790
19 Toth K et. al. The influence of methylated Septin 9 gene on RNA and protein level in
colorectal cancer. 2010, Pathol Oncol Res DOI 10.1007/s12253–010–9338–7.
20 Lo Y et. al. Circulating nucleic acids in plasma and serum: an overview 2001. Ann
NY Acad Sciences.
21 National Center for Biotechnology Information (NCBI). US Library of Medicine,
Bethesda MD, 2012.
RELEVANT PUBLICATIONS ON SEPTIN 9 PLASMA-BASED TESTING
• Payne S et. al. Novel DNA methylation biomarker mSEPT9 for the detection of
colorectal cancer in blood. Future Medicine. 2010, 2(4), 575–585.
• McDade S et. al. Translational control of SEPT9 isoforms is perturbed in disease.
2007 Human Molecular Genetics, 2007, Vol 16, No. 7:742–752.
• Rösch T et. al. Potential of a new blood test for colorectal cancer screening-the
septin9 gene biomarker. Euro Onc. 2010, 6:1–4.
• Grützmann R et. al. Sensitive detection of colorectal cancer in peripheral blood by
Septin9 DNA methylation assay. PLOS ONE. 2008, 3(11):e3759.
• deVos T et. al. Circulating methylated SEPT9 in plasma is a biomarker for colorectal
cancer. Clin Chem. 2009, 55(7):1337–1346.
• Tänzer M et. al. Performance of epigenetic markers SEPT9 and ALX4 in plasma for
selection of colorectal precancerous lesions. PLOS ONE. 2010, 5(2):e9061.
• Toth K et. al. Plasma methylated SEPT9 is a screening marker in both left and rightsided colon cancer: comparison to FOBT and CEA results. DDW, 2012.
• Connolly D et. al. Septin9 isoform expression, localization and epigenetic
changes during human and mouse breast cancer progression. Breast Cancer Res.
2011,13(4): R76.
• Potter N et. al. Validation of a real-time PCR-based qualitative assay for the
detection of methylated SEPT9 DNA in human plasma. Clinical Chemistry. 2014,
60(9):1183-1191.
• Johnson D et. al. Plasma Septin9 versus fecal immunochemical testing for colorectal
cancer screening: prospective multicenter study, PLOS ONE. 2014, 9 (6):1-8.
E98238.
• Adler A et. al. Improving compliance to colorectal cancer screening using bloodbased tests in patients refusing colonoscopy in Germany. BMC Gastro. 2014, Vol
12: 183.
• Pratt V. Are we ready for a blood-based test to detect colon cancer? (editorial). Clin
Chem. 2014, 60(9):1141-1142.
ADDITIONAL SOURCES FOR CLINICAL RELEVANCE OF DNA
METHYLATION
• Calabrese R et. al. Methylation-dependent PAD2 upregulation in multiple sclerosis
peripheral blood. Multiple Sclerosis. 2011, PMID:21878453.
• Cordero P et. al. Leptin and TNF-alpha promoter methylation levels measured by
MSP could predict the response to a low-caloried diet. J. Physio Biochem. 2011,
67(3):463–470.
• Craig J, Wong, N (editor) (2011). Epigenetics: A Reference Manual. Caister
Academic Press.
• Dong E et. al. Clozapine and sulpiride but not haloperidol or olanzapine activate
brain DNA demethylation. Proceedings National Academy Sciences. 2008,
105(36):13614–13619.
• Gallou-Kabani C et. al. Nutritional epigenomics of metabolic syndrome: new
perspective against the epidemic. Diabetes. 2005, 54(7):1899-1906.
• Heijmans B et. al. Persistent epigenetic differences associated with exposure
to prenatal famine in humans. Proceedings National Academy Sciences. 2008,
105(44):17046–17049.
• Ingason A et. al. Maternally derived microduplications at 15q11–q13: implication of
imprinted genes in psychotic illness. Amer J. Psych. 2011, 168(4):408–417.
• Kubota T et. al. Methylation-specific PCR simplifies imprinting analysis. Nature
Genetics. 1997, 16:16-17.
• Maier S et. al. Diabetes: a candidate disease for efficient DNA methylation profiling.
J. Nutrition. 2002, 132(Suppl 8): 2440S–2443S.
• Meda F et. al. The epigenetics of autoimmunity. Cellular Mol Immuno. 2011,
8(3):226–236.
• Mill J et. al. Epigenomic profiling reveals DNA methylation changes associated with
major psychosis. Amer J Human Genetics. 2008, 82(3):696–711.
• Pidsley R et. al. Epigenetic studies of psychosis: current findings, methodological
approaches and implications for postmortem research. Biol Psych. 2011, 69(2):146–
156.
• Pirola L et. al. Genome-wide analysis distinguishes hyperglycemia regulated
epigenetic signatures of primary vascular cells. Genome Research. 2011,
PMID:21890681.
• Pollin T et. al. Epigenetics and diabetes risk: not just for imprinting anymore?
Diabetes. 2011, 60(7):1859–1860.
• Smith F et. al. Regulation of growth and metabolism by imprinted genes. Cytogen
Gen Res. 2006, 113(1–4):279–291.
• Stepanow S et. al. Alle-specific, age-dependent and BMI-associated DNA
methylation of human MCHR1. PLOS ONE. 2011, 6(5):e17711.
• Tobi E et. al. DNA methylation differences after exposure to prenatal famine are
common and timing- and sex-specific. Human Mol Gen. 2009, 18(21):
4046–4053.
• Urdinquio R et. al. Epigenetic mechanisms in neurological diseases: genes,
syndromes and therapies. Lancet Neurology. 2009, 8(11):1056–1072.
• Wang X et. al. Obesity related methylation changes in DNA of peripheral blood
leukocytes. BMC Medicine. 2010, 8:87.
• Zhang C et. al. DNA methyltransferase 3B gene increases risk of early onset
schizophrenia. Neuroscience Letters. 2009, 462(3):308–311.
Epigenomics, Inc.
On-Line: epigenomics.com
Toll free: 844 537 4669 (844-5-EPI NOW)
Corporate Phone: 240 747 7002 Fax: 240 747 7052
Epi proColon® and HeavyMethyl® are registered trademarks of Epigenomics AG, in Europe, USA and/or other selected countries. All other trademarks, brands, names contained herein are
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