Molecular diagnostics using the microbiome in animal health. Designed, executed, and launched a Direct To Consumer (DTC) genomic test--a microbiome test with a clinically actionable reporting goal. Responsible for bringing the NGS laboratory in-house, evaluating and sourcing the appropriate technology (16S rRNA sequencing - Illumina NextSeq & MiniSeq-150PE), designing and executing the appropriate assay to measure the microbiome. I reduced the turnaround time from 6-8 weeks to <2 weeks with a ten-fold increased processing volume while hiring and training a laboratory team.
2. GOAL
Design and execute an affordable, clinically actionable
microbiome test to aid consumers and veterinarians in the
treatment of digestive illnesses and nutritional planning for dogs
and cats.
3. WHAT IS CLINICALLY ACTIONABLE?
Treatment for digestive
illnesses
Timeline of days Validated laboratory
developed test (LDT)
8. TECHNOLOGY
CHOICE: MINISEQ
Two color chemistry
Affordable
Fast
Compare to MiSeq—Legacy technology.
30% more expensive but longer reads.
Illumina.com
9. THE CHALLENGE
• Clinically actionable TAT
(turnaround time) for digestive
illnesses is days.
• NGS tests can take weeks.
• Starting TAT was 6-8 weeks.
• Final TAT goal was 1-2 weeks.
Comeau et al, 2017. mSystems. ASM.
10. GOALS FOR A
DIAGNOSTIC
GENETIC ASSAY
SENSITIVE ACCURATE PRECISE
(REPEATABLE,
REPRODUCIBLE)
TRAINABLE (HANDS
ON TIME,
DIFFICULTY)
ROBUST (HANDS-
ON TIME, MINIMIZE
SOURCES OF ERROR)
CONNECTS TO
ANALYSIS STEPS
EFFICIENTLY
11. TECHNOLOGIES OF INCREASING SENSITIVITY
1
Sanger
Sequencing
—25%
2
QPCR –
10%
160,000
rxns/year
3
Sequenom
MassARRAY
– 3%
30,000
rxns/year
4
Digital PCR—
5% in
synthetic
control
5
CAST-PCR—
0.1 % in
synthetic
control, 3% in
cell lines
6
NGS – 0.1%-
0.05% (2000X)
ION TORRENT
7
Single Cell
Analysis
Technologies
14. SEQUENCING
AMPLICON
PRIMERS
• Fusion primers
• V4 Target = 254 bp
• Dual barcoding (aka indices)
allows multiplexing of up to
384 samples in a single run
• Custom design for Miniseq
Comeau et al, 2017. mSystems. ASM.
16. GOOD LABORATORY PRACTICE, REGULATORY CONCERNS
(FOR DVM AND DIAGNOSTIC MARKETING)
• Pre and post-pcr processes are in physically separate rooms to control for contamination.
• Properly controlled experiments – 16S vs 18S rRNA controls
• Written protocol with version control – Bio-protocol or Protocol.io.
• Positive controls
• Negative controls
17. PHASE 3: LATE RUNS
VALIDATION
STANDARDIZATION
TRAINING
24. ACCURACY AND COMPOSITION - POSITIVE CONTROLS
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
H11 E12 E10b E10 MC* G10 H11_27 H11A F05B
PERCENT
COMPOSITION
SEQ RUN POSITIVE CONTROLS
1. Bacillus 2. Listeria 3. Staphylococcus 4. Lactobacillus 5. Enterococcus
6. Escherichia 7. Pseudomonas 8. Salmonella 9. Other
ZymoBIOMICS Microbial Community DNA Standard
25. KNOWN BIASES IN
16S V4
• Consistent with previous
publications
• Mock community (positive control)
• 16S gene regions show different
taxonomic biases
• Amplicon size is 254 bp
• Accurate to genus
Comeau et al, 2017. mSystems. ASM.
27. ACCURACY & SENSITIVITY CONCLUSIONS OF
16S V4 MICROBIOME ASSAY
Less sensitive with
fewer amplicon
regions.
Accurate to genus
level only. Not
species.
Solutions to improve
accuracy and
sensitivity:
Full 16S Gene - Long
Read technology
(PacBio)
Full 16S gene with
short read technology
using LoopSeq
Whole Genome
Shotgun Sequencing