medRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 19, 2025
Abstract
Population-scale
single-cell
transcriptomic
technologies
(scRNA-seq)
enable
characterizing
variant
effects
on
gene
regulation
at
the
cellular
level
(e.g.,
eQTLs;
sc-eQTLs).
However,
existing
sc-eQTL
mapping
approaches
are
either
not
designed
for
analyzing
sparse
counts
in
scRNA-seq
data
or
can
become
intractable
extremely
large
datasets.
Here,
we
propose
jaxQTL,
a
flexible
and
efficient
framework
using
highly
count-based
models
given
pseudobulk
data.
Using
extensive
simulations,
demonstrated
that
jaxQTL
with
negative
binomial
model
outperformed
other
identifying
sc-eQTLs,
while
maintaining
calibrated
type
I
error.
We
applied
across
14
cell
types
of
OneK1K
(
N
=982),
identified
11-16%
more
eGenes
compared
approaches,
primarily
driven
by
ability
to
identify
lowly
expressed
eGenes.
observed
fine-mapped
sc-eQTLs
were
further
from
transcription
starting
site
(TSS)
than
eQTLs
all
cells
(bulk-eQTLs;
P
=1×10
−4
)
enriched
cell-type-specific
enhancers
=3×10
−10
),
suggesting
improve
our
distal
missed
bulk
tissues.
Overall,
genetic
effect
largely
shared
types,
cell-type-specificity
increasing
distance
TSS.
Lastly,
explain
SNP-heritability
h
2
bulk-eQTLs
(9.90
±
0.88%
vs.
6.10
0.76%
when
meta-analyzed
16
blood
immune-related
traits),
improving
but
closing
missing
link
between
GWAS
eQTLs.
As
an
example,
highlight
T
(unlike
bulk-eQTLs)
successfully
nominate
IL6ST
as
candidate
rheumatoid
arthritis.
provides
powerful
approach
disease-associated
The American Journal of Human Genetics,
Journal Year:
2022,
Volume and Issue:
109(2), P. 223 - 239
Published: Jan. 31, 2022
Uncovering
the
functional
impact
of
genetic
variation
on
gene
expression
is
important
in
understanding
tissue
biology
and
pathogenesis
complex
traits.
Despite
large
efforts
to
map
quantitative
trait
loci
(eQTLs)
across
many
human
tissues,
our
ability
translate
those
findings
disease
has
been
incomplete,
majority
are
not
explained
by
association
with
a
target
gene.
Cell-type
specificity
presence
multiple
independent
causal
variants
for
eQTLs
potential
confounders
contributing
apparent
discrepancy
loci.
In
this
study,
we
investigate
effects
overlap
while
considering
within
tissues.
We
find
evidence
pervasive
eQTLs,
often
masked
linkage
disequilibrium
that
misleads
traditional
meta-analytic
approaches.
propose
CAFEH
(colocalization
fine-mapping
allelic
heterogeneity),
Bayesian
method
integrates
data
traits,
incorporating
identify
variants.
outperforms
previous
approaches
colocalization
fine-mapping.
Using
CAFEH,
show
genes
highly
tissue-specific
under
greater
selection,
enriched
differentiation
developmental
processes,
more
likely
be
involved
disease.
Last,
demonstrate
can
efficiently
leverage
widespread
heterogeneity
regulation
prioritize
genome-wide
loci,
thereby
improving
interpret
genetics.
Annual Review of Genomics and Human Genetics,
Journal Year:
2023,
Volume and Issue:
24(1), P. 277 - 303
Published: May 17, 2023
Recent
advancements
in
single-cell
technologies
have
enabled
expression
quantitative
trait
locus
(eQTL)
analysis
across
many
individuals
at
resolution.
Compared
with
bulk
RNA
sequencing,
which
averages
gene
cell
types
and
states,
assays
capture
the
transcriptional
states
of
individual
cells,
including
fine-grained,
transient,
difficult-to-isolate
populations
unprecedented
scale
Single-cell
eQTL
(sc-eQTL)
mapping
can
identify
context-dependent
eQTLs
that
vary
some
colocalize
disease
variants
identified
genome-wide
association
studies.
By
uncovering
precise
contexts
these
act,
approaches
unveil
previously
hidden
regulatory
effects
pinpoint
important
underlying
molecular
mechanisms
disease.
Here,
we
present
an
overview
recently
deployed
experimental
designs
sc-eQTL
In
process,
consider
influence
study
design
choices
such
as
cohort,
ex
vivo
perturbations.
We
then
discuss
current
methodologies,
modeling
approaches,
technical
challenges
well
future
opportunities
applications.
Cell Genomics,
Journal Year:
2024,
Volume and Issue:
4(4), P. 100538 - 100538
Published: April 1, 2024
Nearly
all
trait-associated
variants
identified
in
genome-wide
association
studies
(GWASs)
are
noncoding.
The
cis
regulatory
effects
of
these
have
been
extensively
characterized,
but
how
they
affect
gene
regulation
trans
has
the
subject
fewer
because
difficulty
detecting
trans-expression
quantitative
loci
(eQTLs).
We
developed
trans-PCO
for
genetic
on
networks.
Our
simulations
demonstrate
that
substantially
outperforms
existing
trans-eQTL
mapping
methods.
applied
to
two
expression
datasets
from
whole
blood,
DGN
(N
=
913)
and
eQTLGen
31,684),
14,985
high-quality
trans-eSNP-module
pairs
associated
with
197
co-expression
modules
biological
processes.
performed
colocalization
analyses
between
GWAS
46
complex
traits
trans-eQTLs.
demonstrated
can
help
us
understand
networks
pathways.
medRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 17, 2025
Abstract
Background
Genome-wide
association
studies
(GWAS)
have
identified
hundreds
of
loci
underlying
adult-onset
asthma
(AOA)
and
childhood-onset
(COA).
However,
the
causal
variants,
regulatory
elements,
effector
genes
at
these
are
largely
unknown.
Methods
We
performed
heritability
enrichment
analysis
to
determine
relevant
cell
types
for
AOA
COA,
respectively.
Next,
we
fine-mapped
putative
variants
COA
loci.
To
improve
resolution
fine-mapping,
integrated
ATAC-seq
data
in
blood
lung
annotate
candidate
cis
-regulatory
elements
(CREs).
then
computationally
prioritized
CREs
risk,
experimentally
assessed
their
enhancer
activity
by
massively
parallel
reporter
assay
(MPRA)
bronchial
epithelial
cells
(BECs)
further
validated
a
subset
luciferase
assays.
Combining
chromatin
interaction
expression
quantitative
trait
loci,
nominated
targeted
COA.
Results
Heritability
suggested
shared
role
immune
development
both
while
highlighting
distinct
contribution
structural
Functional
fine-mapping
uncovered
21
67
credible
sets
respectively,
with
only
16%
between
two.
Notably,
one-third
contained
multiple
sets.
Our
CRE
prioritization
strategy
62
169
Over
60%
showed
open
lineages,
suggesting
potential
pleiotropic
effects
different
types.
Furthermore,
were
enriched
enhancers
MPRA
BECs.
The
included
many
involved
inflammatory
responses.
genes,
including
TNFSF4
,
drug
target
undergoing
clinical
trials,
supported
two
independent
GWAS
signals,
indicating
widespread
allelic
heterogeneity.
Four
out
six
selected
demonstrated
allele-specific
properties
assays
Conclusions
present
comprehensive
characterization
genetics.
results
genetic
basis
highlighted
complexity
marked
extensive
pleiotropy
Journal of Clinical Investigation,
Journal Year:
2025,
Volume and Issue:
135(5)
Published: March 2, 2025
Exposure
to
traumatic
stress
is
common
in
the
general
population.
Variation
brain's
molecular
encoding
of
potentially
contributes
heterogeneous
clinical
outcomes
response
experiences.
For
instance,
only
a
minority
those
exposed
trauma
will
develop
post-traumatic
disorder
(PTSD).
Risk
for
PTSD
at
least
partially
heritable,
with
growing
number
genetic
factors
identified
through
GWAS.
A
major
limitation
studies
that
they
capture
component
risk,
whereas
by
definition
requires
an
environmental
exposure.
Furthermore,
extent,
timing,
and
type
affects
susceptibility.
Here,
we
discuss
mechanisms
risk
together
gene
×
environment
interactions,
focus
on
how
either
might
inform
screening
individuals
high
disease,
reveal
biological
one
day
yield
novel
therapeutics,
impact
best
practices
even
today.
To
close,
interaction
sex,
gender,
race,
implications
treatment.
Altogether,
suggest
predicting,
preventing,
treating
require
integrating
both
genotypic
information.
bioRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: March 21, 2023
Abstract
Common
genetic
variants
confer
substantial
risk
for
chronic
lung
diseases,
including
pulmonary
fibrosis
(PF).
Defining
the
control
of
gene
expression
in
a
cell-type-specific
and
context-dependent
manner
is
critical
understanding
mechanisms
through
which
variation
influences
complex
traits
disease
pathobiology.
To
this
end,
we
performed
single-cell
RNA-sequencing
tissue
from
67
PF
49
unaffected
donors.
Employing
pseudo-bulk
approach,
mapped
quantitative
trait
loci
(eQTL)
across
38
cell
types,
observing
both
shared
type-specific
regulatory
effects.
Further,
identified
disease-interaction
eQTL
demonstrated
that
class
associations
more
likely
to
be
cell-type
specific
linked
cellular
dysregulation
PF.
Finally,
connected
their
targets
disease-relevant
types.
These
results
indicate
context
determines
impact
on
expression,
implicates
context-specific
as
key
regulators
homeostasis
disease.
Science Immunology,
Journal Year:
2021,
Volume and Issue:
6(64)
Published: Oct. 13, 2021
The
germinal
center
(GC)
response
is
critical
for
both
effective
adaptive
immunity
and
establishing
peripheral
tolerance
by
limiting
autoreactive
B
cells.
Dysfunction
in
these
processes
can
lead
to
defective
immune
responses
infection
or
contribute
autoimmune
disease.
To
understand
the
gene
regulatory
principles
underlying
GC
response,
we
generated
a
single-cell
transcriptomic
epigenomic
atlas
of
human
tonsil,
widely
studied
representative
lymphoid
tissue.
We
characterize
diverse
cell
subsets
build
trajectory
dynamic
expression
transcription
factor
activity
during
activation,
formation,
plasma
differentiation.
subsequently
leverage
type–specific
maps
interpret
potential
impact
genetic
variants
implicated
autoimmunity,
revealing
that
many
exhibit
their
greatest
GC-associated
cellular
populations.
These
included
loci
linked
with
known
roles
biology
(
Genetics,
Journal Year:
2024,
Volume and Issue:
228(1)
Published: July 26, 2024
Abstract
Most
gene
expression
and
alternative
splicing
quantitative
trait
loci
(eQTL/sQTL)
studies
have
been
biased
toward
European
ancestry
individuals.
Here,
we
performed
eQTL
sQTL
analyses
using
TOPMed
whole-genome
sequencing-derived
genotype
data
RNA-sequencing
from
stored
peripheral
blood
mononuclear
cells
in
1,012
African
American
participants
the
Jackson
Heart
Study
(JHS).
At
a
false
discovery
rate
of
5%,
identified
17,630
unique
credible
sets
covering
16,538
genes;
24,525
9,605
genes,
with
lead
QTL
at
P
<
5e−8.
About
24%
independent
eQTLs
sQTLs
minor
allele
frequency
>
1%
JHS
were
rare
(minor
0.1%),
therefore
unlikely
to
be
detected,
Finally,
created
an
open
database,
which
is
freely
available
online,
allowing
fast
query
bulk
download
our
results.