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This presentation summarizes genomics technologies and how they are currently being used in the personal care industry.
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Application of Genomics Tools for
Personal Care Product Development
Anna Langerveld, PhD
IMSCC Scientific Meeting
August, 2010
www.genemarkersllc.com
Phone: 269-365-9006
Overview of Presentation
Genemarkers Capabilities
Genomics
◦ History & brief overview of molecular biology
◦ Current applications in personal care
Commonly Used Genomics Methods in Personal Care
◦ Microarrays
◦ PCR
Good Study Design & Interpreting Data
Genemarkers LLC
Founded in 2007; privately funded
◦ Biotech spin-off from Western Michigan University
Currently lease lab space from MI hospital research facility
Personnel are highly skilled with many years experience with
genomics technologies
Established working collaborations with local biotech businesses to
expand capabilities
◦ Hospital run research lab provides histology services
◦ Michigan High Throughput Screening Center (MHTSC) – cell
culture facility, cell culture assays
◦ Statistical/bioinformatics experts
Genemarkers LLC
Provide contract research services
◦ Wide range of projects – study sponsors include:
Large, mid and small-sized personal care/skin care companies
Large pharma
Medical device
Biotech and molecular diagnostic development companies
Academics
In-house project to develop a molecular diagnostic test to differentiate rare forms of Parkinson’s disease (multiple system atrophy)
◦ Collaboration with researchers at Western Michigan University and Vanderbilt University Medical School
Genemarkers Personal Care Services
Gene expression, genotyping (SNP analysis), microRNA expression
◦ Affymetrix
◦ Applied Biosystems Taqman methods
Qualified testing lab to perform MatTek Skin Irritancy Test (SIT assay)
◦ MTT assay
Cell culture capabilities
Process many types of cells and tissues; human skin punch biopsies, hair
Genomics assays for assessing sun damage
◦ Measure induction of mitochondrial common deletion
◦ p53 gene expression
◦ p53 SNP analysis
Study Design and Planning
Sample Processing
Data Analysis and
Interpretation
GenomicsHistory and Applications in Personal Care
Genomics: History and Current Applications
Field was born from the human genome project
◦ identified and sequenced ~20,000 - 30,000 human genes
◦ 2000 first draft of human genome was published
Produced high throughput technologies that measure/analyze:
◦ Gene expression (which genes are turned on or off in a given condition)
◦ Gene sequence (determines if the DNA code is altered)
SNP’s – single nucleotide polymorphisms
Technologies are being used in all areas of human health (personalized
medicine), animal health, environmental and agricultural industries
Rapidly emerging in the personal care industry
Increasing Use of Genomics Language
in Marketing to Consumers
Novel Ingredient – “skingenecell”
Increase in Gene Expression Data Presented to
Formulators by Ingredient Suppliers
The Biological Basis of Skin Characteristics: How
Do Genes Relate to the Skin’s Appearance?
Physical Characteristics
Fine lines, wrinkles, age spots, dullness
Changes in Biological/Physiological Processes
Inflammation, cell cycle/regeneration,
oxidant formation/anti-oxidant production, aging molecules,
extracellular matrix integrity
Changes in gene expression and protein expression
(sirtuins, collagens, keratins, growth factors,
metalloproteinases, interleukins)
= Biomarkers
Bio
mar
kers
Current Applications of Genomics-Based
Methods in Personal Care
Efficacy & Claims Support
Product Development
Safety Assessment
Personalized Skin Care
The Benefits of Genomics Methods for
Efficacy and Claims Support
Determine how specific ingredients or finished products regulate gene
expression
◦ For example, product may benefit skin by increasing expression of
COL1A1 and decrease expression of MMP1 = “anti-aging”
Characterize molecular mechanisms of action
◦ Inflammation (redness) produced through multiple biological
pathways; i.e. TNF- , IL-1
◦ Define how your product works more specifically
The Benefits of Genomics Methods for
Product Development
Identify gene expression signatures/profiles of specific conditions and/or
diseases (old vs young skin)
◦ Specific genes become “targets” for product development
◦ Scientifically sound approach to achieving product’s goals
Identify dose response relationships to conserve the use of costly
ingredients
◦ For example, anti-oxidants typically more effective at lower doses
◦ Organic ingredients can be expensive
Understand how combinations of ingredients work together
◦ For example, if you add 5 actives, do you get a 5X response?
GENOMICS
GENOTYPING & GENE
EXPRESSION
Genotyping: Analysis of DNA Code
• All cells in the human body have 23 pairs of chromosomes
• Chromosomes comprised of DNA/genes
• DNA is comprised of a “code” that contains combinations of 4 bases
(Adenine, Thymine, Guanine, Cytosine)
• Analysis of “code” = gene sequencing/genotyping
• Approximately 1% difference in DNA sequence accounts for individual
differences in people
Gene Expression is Based on the Central Dogma
of Biology
All cells in a person’s body have the same DNA or “genes”
When the gene is activated it is turned into RNA
Different cell types are produced by activation of unique sets of genes
Specific RNAs assemble specific proteins such as collagen and keratin in skin cells
Aging, disease and other conditions will influence the regulation of specific genes
Gene expression technologies measure the amount of RNA in a given cell or tissue
Different Patterns of Gene Expression
Produce Unique Cell Types
NeuronRed Blood Cells
•Each of these cell types has the same DNA
•Different genes are “turned on or off” to produce the different cell types
•Similarly, patterns of gene expression change within a cell type as cells age or
are exposed to different conditions (i.e., disease, treatments, etc.)
Gene expression = RNA “amount”
DNA RNA
ProteinsNucleus
Cell membrane
DNA RNA
ProteinsNucleus
Cell membrane
Untreated Treated
Gene expression technologies measure the amount of specific
RNAs within a cell or tissue
2 PRIMARY TECHNOLOGIES FOR
MEASURING GENE EXPRESSION
1. Microarrays (large screen)
2. Quantitative PCR (qPCR; smaller numbers of genes)
Genomics Experimental Workflow
Treat cells, tissues, subjects with test article
Isolate RNA
cDNA synthesis
qPCR
Analysis
Data Analysis
Array sample labeling
Array Processing
Data Analysis
qPCR Microarray
2 Basic Microarray Platforms
Slide based systems
Multiple companies
Up to several thousand genes on a
slide
Affymetrix GeneChip
Up to 45,000 transcripts
•Use different chemistry systems and have different levels of sensitivity and detection
•Significant differences in cost
•Similar principle – gene specific “probes” (DNA) are placed on matrix, sample hybridized to the
probe
Affymetrix Microarrays (GeneChips)
Measure up to 45,000 transcripts at a time
Chips available for over 30 organisms
Ideal for discovery-based studies
◦ What does my product/ingredient do?
◦ Identifying novel mechanisms of action
◦ Building database of gene expression signatures of different conditions
Used as a screening tool; results are often confirmed with qPCR
ProbeArrays(chips)
GeneChip®
System
Scanner
Scanner
SoftwareData Analysis
FluidicsStation
Affymetrix Sample Processing
Overview
Hybridization of sample (purple) to probes (green) on chip
Complementary (matched)
sequences will form pair
Unmatched sequences will
not bind to chip
Affymetrix GeneChip® Data
Bioinformatics
Multiple software programs to analyze the data
◦ Affymetrix Gene Command Console (AGCC), GeneSpring
Statistical data analysis to identify genes that are upregulated and
downregulated
◦ Fold change value that quantifies the change relative to a control
sample
Datasets are further analyzed to sort genes into biological functions
and pathways
Tools for Visualizing/Analyzing Microarray Data
Heatmaps/Cluster
Analyses
Venn Diagrams
Compare Treatment
Group DatasetsBiological Pathway Analysis
PCRPolymerase Chain Reaction
PCR – Polymerase Chain Reaction
Method for amplifying specific regions of DNA/genes
Used to identify
◦ changes in DNA sequence
◦ changes in gene expression
PCR methods have evolved dramatically over the past 15-20 years
◦ More sensitive
◦ Automated and highly reproducible
◦ More quantitative (semi-quantitative to quantitative real time PCR)
Similar to microarrays, there are different instrumentation platforms and different chemistries
◦ SYBR Green
◦ Fluorescent probes
◦ Taqman probes
Taqman Real Time PCR (Polymerase Chain
Reaction)
Taqman Low Density Array (TLDA)
Less expensive than microarrays; very sensitive method – highly quantifiable
Can measure up to 384 genes at a time
Arrays are custom-designed with your genes of interest
More focused experimental approach
Taqman Real Time PCR
Each target gene (i.e., COL1A1) is amplified using a set of primers and a fluorescent labeled probe that contain complementary sequences (DNA code) to the gene of interest
The probe contains a fluorescent reporter dye (R) on one end and a quencher dye (Q) that inhibits the fluorescent signal
As the reaction DNA synthesis reaction proceeds, the quencher is displaced from the probe, causing the an increase in fluorescent signal
The instrument reads the level of fluorescence in each well every 7 seconds and records this data in real time
Samples with greater amounts of starting material will produce more copies of DNA and will emit greater levels of fluorescence
Taqman PCR Data Analysis
The PCR reaction takes place over 40 cycles and fluorescent signal is recorded with regard to cycle number
Rn refers to the level of fluorescence
A threshold line is drawn during the “amplification phase” of the PCR reaction (red line)
◦ Amplification phase refers to the point during which the amplification takes place exponentially
◦ Other phases refer to baseline or plateau and are not the best phases to compare samples
The cycle at which the sample crosses the threshold line is called the Ct value
Ct values are compared for each sample
Samples that have lower Ct values amplify at a faster rate and thus, have greater amounts of starting material (RNA) for the target gene
◦ Sample 1 > Sample 2
Sample 2
Sample 1
qPCR Data Analysis Results
Results are expressed in “relative quantitative” values
◦ Value (Ct) of target gene is first normalized to an endogenous
control gene (reference)
Delta Ct
◦ Relative = “treated” compared to a “control”
Log10RQ
Statistics (t-tests) used to identify statistically significant changes in
gene regulation
Provide p-value, direction, fold change value (log scale – log10RQ)
Presentation of qPCR Results
*
*
*
qPCR results are often presented using bar graphs that show increased or
decreased gene expression
Graphs may show data in LOG10RQ or linear format
Figure captions should describe study and statistical results
* Statistically significant at p<0.01, N=4
Evaluating Study Results
Replicates; large enough sample size for statistical data analysis
◦ Figures, data presentation will show p values, special symbol for results that are statistically significant
Appropriate controls included in the study
◦ For example, if dissolving ingredient in a solvent, the solvent alone should be included in the analysis
◦ Some studes include a positive control
With qRT-PCR analyses, the results are typically normalized to an endogenous control gene; a gene that shows stable expression in all of the samples (regardless of treatment)
◦ ****Very important to screen endogenous control genes to identify a stable gene
◦ Not always the same in all studies
◦ Most studies will select 18S, GAPDH or -actin based on “old school” dogma that these genes are stable
◦ More current data shows these 3 are not always the best choices
◦ Results can be very different based on endogenous control gene choice
Studies with good design and robust methods will show optimization parameters in report, while others will merely omit these details
Example of Endogenous Control Gene
Amplification
18S
GUSBGAPDH
HPRT
In this study, 18S showed the least variability in amplification between
samples and was the best endogenous control gene
Example of Endogenous Control Gene
Amplification
In this study, the treatment
influenced expression of
GAPDH and -actin
◦ The top figure shows 2 clearly
different patterns of
amplification
Our screening process
identified GUSB and PPIA as
the best endogenous
control genes for the study
◦ The bottom figure shows similar
amplification profiles for the
samples in the study
GAPDH -actin
GUSB PPIA
Benefits of Genomics-Based Studies to the
Personal Care Industry
Use genomics information to guide product formulation
◦ identify specific molecular targets for achieving desired effects
Cost-savings
◦ Identify dose-response relationships
◦ May find that a small amount of expensive ingredient produces same effect as higher concentration
Validate efficacy
Ensure product safety
◦ Identification of validated safety biomarkers
◦ Negative response on established toxicity markers
Ultimately, improve marketability and consumer confidence
Contact information Phone: 269-365-9006
www.genemarkersllc.com