Research

rs1360780 — FKBP5 Intronic C>T

Co-chaperone of the glucocorticoid receptor that regulates cortisol feedback — the T allele impairs stress recovery and, combined with early adversity, strongly increases risk of PTSD and depression

Strong Risk Factor

Details

Gene
FKBP5
Chromosome
6
Risk allele
T
Consequence
Regulatory
Inheritance
Codominant
Clinical
Risk Factor
Evidence
Strong
Chip coverage
v3 v4 v5

Population Frequency

CC
45%
CT
44%
TT
11%

Ancestry Frequencies

african
43%
south_asian
32%
european
31%
latino
28%
east_asian
25%

The Stress Recovery Gene — Why Some People Bounce Back Faster

Your body's stress response is meant to be temporary. When a threat appears, the HPA axis11 HPA axis
The hypothalamic-pituitary-adrenal axis: a hormonal cascade where the hypothalamus signals the pituitary, which signals the adrenal glands to release cortisol. It is the body's central stress response system
floods your bloodstream with cortisol22 cortisol
The primary stress hormone. Cortisol raises blood sugar, suppresses the immune system, and aids metabolism of fat, protein, and carbohydrates. Chronically elevated cortisol damages the hippocampus and increases risk of depression, anxiety, and cardiovascular disease
, and when the threat passes, cortisol is supposed to shut itself off through a negative feedback loop. The gene FKBP5 is a critical gatekeeper of that off switch, and the rs1360780 variant determines how effectively it works.

FKBP5 encodes a co-chaperone33 co-chaperone
A helper protein that assists chaperone proteins (like hsp90) in folding other proteins into their correct shape. FKBP5 specifically helps regulate the glucocorticoid receptor
called FK506 Binding Protein 51 that regulates the glucocorticoid receptor44 glucocorticoid receptor
The intracellular receptor for cortisol. When cortisol binds GR in the cytoplasm, the receptor complex travels to the nucleus and activates or represses hundreds of genes — including FKBP5 itself
(GR). This variant is one of the strongest gene-environment findings in all of psychiatry: the T allele combined with childhood adversity dramatically increases risk for PTSD, depression, and anxiety. Without adversity, carriers typically show no increased risk — making this a textbook example of how genes and experience interact.

The Mechanism

The rs1360780 variant sits in intron 2 of FKBP5, within a region that functions as a glucocorticoid response element55 glucocorticoid response element
A DNA sequence where the activated glucocorticoid receptor binds to turn genes on or off. GREs are how cortisol changes gene expression throughout the body
(GRE). The T allele creates a stronger GRE that binds the TATA-box binding protein66 TATA-box binding protein
A general transcription factor that helps initiate gene transcription. Stronger TATA-box binding means more efficient gene activation
more effectively, enhancing a long-range chromatin interaction77 chromatin interaction
Physical contact between distant regions of DNA within the nucleus. In this case, the intron 2 enhancer loops to contact the FKBP5 promoter, boosting transcription
between this intronic enhancer and the FKBP5 promoter. The result: when cortisol rises, T-allele carriers produce roughly twice as much FKBP5 protein as C-allele carriers.

This creates a vicious cycle. More FKBP5 protein inhibits GR from translocating to the nucleus, which reduces cortisol's ability to activate the negative feedback that would shut down its own production. The stress response therefore takes longer to resolve — cortisol stays elevated, and the person remains in a physiological state of stress even after the triggering event has passed.

The Klengel et al. 201388 Klengel et al. 2013
Klengel T et al. Allele-specific FKBP5 DNA demethylation mediates gene-childhood trauma interactions. Nature Neuroscience, 2013
study revealed an additional layer: in T-allele carriers who experienced childhood trauma, a second GRE in intron 7 undergoes allele-specific demethylation99 allele-specific demethylation
Removal of methyl groups from DNA at specific sites, but only on the chromosome carrying the T allele. This epigenetic change is persistent and makes FKBP5 even more responsive to cortisol in the future
. This epigenetic change is persistent — it locks FKBP5 into a state of heightened responsiveness, permanently amplifying the stress feedback dysfunction. Critically, this demethylation only occurs during sensitive developmental periods and only in T-allele carriers, explaining why the same genotype produces different outcomes depending on life experience.

The Evidence

The foundational study by Binder et al.1010 Binder et al.
Binder EB et al. Polymorphisms in FKBP5 are associated with increased recurrence of depressive episodes and rapid response to antidepressant treatment. Nature Genetics, 2004
first identified rs1360780 as the FKBP5 variant most strongly associated with recurrent depression and, paradoxically, faster antidepressant response (N=294 inpatients). TT homozygotes reported more depressive episodes but responded to antidepressants more quickly over a 5-week treatment course.

The landmark gene-environment study came from Binder et al. 20081111 Binder et al. 2008
Binder EB et al. Association of FKBP5 polymorphisms and childhood abuse with risk of posttraumatic stress disorder symptoms in adults. JAMA, 2008
, examining over 900 individuals from an urban, low-income population. Four FKBP5 SNPs (including rs1360780) significantly interacted with childhood abuse severity to predict adult PTSD symptoms — but showed no direct main effect on PTSD without the environmental trigger. Dexamethasone suppression testing confirmed genotype-dependent differences in GR sensitivity.

A meta-analysis of 14 studies1212 meta-analysis of 14 studies
Wang Q et al. Interaction between early-life stress and FKBP5 gene variants in major depressive disorder and post-traumatic stress disorder. J Affect Disord, 2018
pooling 15,109 participants confirmed that rs1360780 T-allele carriers exposed to early-life trauma have significantly higher risk for depression and PTSD. A separate meta-analysis of MDD susceptibility1313 meta-analysis of MDD susceptibility
Rao S et al. Common variants in FKBP5 gene and major depressive disorder susceptibility. Sci Rep, 2016
(N=26,582) found a modest direct association (OR 1.06, P=0.003), underscoring that the genetic effect alone is small — the risk emerges primarily through gene-environment interaction.

Beyond psychiatric risk, Fujii et al.1414 Fujii et al.
Fujii T et al. The common functional FKBP5 variant rs1360780 is associated with altered cognitive function in aged individuals. Sci Rep, 2014
found that T-allele carriers over age 50 showed significantly poorer working memory and attention (N=742), consistent with the known neurotoxic effects of chronic cortisol elevation on the hippocampus. And Zannas et al.1515 Zannas et al.
Zannas AS et al. Epigenetic upregulation of FKBP5 by aging and stress contributes to NF-kB-driven inflammation and cardiovascular risk. PNAS, 2019
demonstrated that age- and stress-related FKBP5 upregulation drives chronic inflammation through NF-kB signaling, linking this variant to cardiovascular risk in cohorts totaling over 3,000 individuals.

Practical Implications

The most important message from this research is that rs1360780 is not a deterministic "risk gene" — it is an amplifier that magnifies the biological impact of stress, especially early-life stress. T-allele carriers who grow up in supportive, low-adversity environments show no elevated psychiatric risk. This makes stress management not just helpful but genetically indicated for carriers.

Regular aerobic exercise is one of the most evidence-based interventions: it improves cortisol regulation, boosts BDNF1616 BDNF
Brain-derived neurotrophic factor, a protein that supports neuron growth and survival. Exercise increases BDNF by 200-300%, counteracting cortisol's neurotoxic effects on the hippocampus
, and can alter FKBP5 methylation patterns within 8-12 weeks. Mindfulness-based stress reduction has been shown to improve HPA axis regulation and reduce FKBP5-related inflammatory signaling. For carriers who have experienced significant adversity, trauma-focused therapy (such as EMDR or prolonged exposure therapy) addresses the epigenetic consequences directly.

The paradoxical finding that TT carriers respond faster to antidepressants is clinically relevant: if a T-carrier develops depression, this information may support confidence in trying pharmacotherapy, as the same HPA axis sensitivity that increases vulnerability may also accelerate treatment response.

Interactions

rs1360780 is in strong linkage disequilibrium with three other FKBP5 SNPs: rs9296158, rs3800373, and rs9470080. Together they form a functional haplotype that determines FKBP5 induction capacity. Most studies genotype all four, and the risk effects are highly correlated (D' > 0.9).

A potential interaction with COMT (rs4680) is worth noting: FKBP5 T-carriers with COMT Met/Met genotype (slow catecholamine clearance) may experience compounded stress vulnerability — the hormonal stress response (cortisol via HPA axis) and the neurotransmitter stress response (dopamine/norepinephrine via COMT) are both prolonged. This combination would benefit most from structured daily stress management practices.

BDNF (rs6265) represents another relevant interaction: since chronic cortisol elevation damages the hippocampus, and the BDNF Val66Met variant reduces activity-dependent BDNF secretion, carriers of both risk alleles may be particularly vulnerable to stress-related cognitive decline and would benefit especially from regular aerobic exercise, which independently boosts BDNF.

Genotype Interpretations

What each possible genotype means for this variant:

CC “Normal Stress Recovery” Normal

Normal cortisol feedback — standard stress recovery

The C/C genotype at rs1360780 results in normal FKBP5 transcriptional response to glucocorticoid receptor activation. Without the T allele's enhanced GRE in intron 2, the cortisol-FKBP5-GR feedback loop operates at baseline efficiency. Studies consistently show that C/C carriers exposed to childhood adversity do not show the elevated PTSD and depression risk seen in T-allele carriers under the same conditions (Binder et al., 2008). Dexamethasone suppression testing confirms normal GR sensitivity in this genotype. The intron 7 CpG sites maintain normal methylation levels regardless of early-life experience, as the allele-specific demethylation mechanism requires the T allele on at least one chromosome.

CT “Stress Sensitive” Intermediate Caution

One copy of the stress-sensitivity allele — moderately impaired cortisol feedback

The heterozygous C/T genotype produces an intermediate level of FKBP5 induction following cortisol release. One chromosome carries the enhanced GRE that drives stronger FKBP5 transcription, resulting in moderately elevated FKBP5 protein and correspondingly reduced GR nuclear translocation efficiency. The Binder et al. (2008) JAMA study showed that CT carriers with high childhood abuse exposure had significantly elevated PTSD symptoms compared to CC carriers with the same exposure — though the effect was smaller than for TT homozygotes.

The Klengel et al. (2013) epigenetic findings apply here too: the T-carrying chromosome can undergo allele-specific demethylation at intron 7 CpG sites following childhood trauma, creating a persistent epigenetic mark that increases future FKBP5 stress responsiveness. This effect is present but less pronounced than in TT carriers.

The Fujii et al. (2014) cognitive study found intermediate working memory effects in CT carriers over age 50, consistent with a dose-dependent cortisol impact on hippocampal function.

TT “High Stress Sensitivity” High Risk Warning

Two copies of the stress-sensitivity allele — significantly impaired cortisol feedback

The TT genotype at rs1360780 produces the highest level of cortisol- induced FKBP5 transcription. Both chromosomes carry the enhanced GRE in intron 2, leading to approximately 2-fold higher FKBP5 protein levels compared to CC carriers following glucocorticoid exposure. This creates maximal inhibition of GR nuclear translocation and the most impaired negative feedback of the HPA axis.

In the Binder et al. (2008) JAMA study, TT carriers with severe childhood abuse showed the highest PTSD symptom levels of any genotype-exposure group. The Klengel et al. (2013) Nature Neuroscience study demonstrated that both chromosomes undergo intron 7 demethylation following childhood trauma exposure, creating a particularly strong and persistent epigenetic amplification of the stress response.

The Fujii et al. (2014) study in 742 Japanese individuals found that TT carriers over age 50 had the poorest attention and working memory scores, consistent with cumulative hippocampal effects of chronic cortisol elevation. The Zannas et al. (2019) PNAS study further showed that FKBP5 upregulation drives NF-kB-mediated inflammation, linking this genotype to cardiovascular risk through a stress- inflammation pathway.

A clinically important paradox: despite increased depression vulnerability, TT carriers show the fastest response to antidepressant treatment (Binder et al., 2004). The same HPA axis sensitivity that amplifies stress may also make the system more responsive to pharmacological intervention.

Key References

PMID: 15565110

Binder et al. 2004 — landmark Nature Genetics study linking FKBP5 polymorphisms including rs1360780 to recurrent depression and rapid antidepressant response (N=294 inpatients)

PMID: 18349090

Binder et al. 2008 — JAMA study demonstrating FKBP5 x childhood abuse interaction on PTSD risk in 900+ individuals; genotype-dependent glucocorticoid sensitivity confirmed by dexamethasone suppression

PMID: 23201972

Klengel et al. 2013 — Nature Neuroscience study showing allele-specific FKBP5 DNA demethylation in intron 7 mediates gene-childhood trauma interaction; T-allele carriers exposed to early trauma show persistent epigenetic changes

PMID: 28850857

Wang et al. 2018 — meta-analysis of 14 studies (N=15,109) confirming FKBP5 rs1360780 T-allele x early-life stress interaction increases risk for depression and PTSD

PMID: 25331639

Fujii et al. 2014 — rs1360780 T-allele associated with poorer working memory and attention in aged individuals (>50 years) in 742 Japanese subjects

PMID: 31113877

Zannas et al. 2019 — PNAS study showing FKBP5 epigenetic upregulation by aging and stress drives NF-kB inflammation and cardiovascular risk across cohorts totaling >3,000 individuals

PMID: 27601205

Rao et al. 2016 — meta-analysis of FKBP5 variants and MDD susceptibility (N=26,582); rs1360780 T-allele associated with MDD (OR 1.06, P=0.003)