rs34579341 — NEGR1 NEGR1 Neuronal Growth Regulator

The Dual Mood-Metabolic Gene — NEGR1 and the Neuron Wiring That Links Depression to Body Weight

At the intersection of brain chemistry and body weight lies a gene most people have never heard of. NEGR1¹¹ NEGR1
Neuronal Growth Regulator 1 — a GPI-anchored cell adhesion molecule belonging to the IgLON superfamily. It is expressed on the neuronal surface and regulates the physical contacts between developing neurons encodes a molecular "social glue" that neurons use to recognize and bond with each other. Variants in NEGR1 have been replicated across virtually every major depression genome-wide association study (GWAS) of the past decade, making it one of the most robust genetic risk genes for mood disorders identified to date. What makes NEGR1 unusual is that it also shows up in obesity GWAS — hinting that the same hypothalamic wiring that shapes emotional resilience also governs feeding behavior and energy balance.

The Mechanism

NEGR1 belongs to the IgLON family²² IgLON family
A family of immunoglobulin-domain cell adhesion molecules (CAMs) including LSAMP, OPCML, NRCAM, NEGR1, and NTROPHY that regulate neuronal connectivity during development and in the adult brain. Each family member has three immunoglobulin domains and a GPI anchor attaching it to the outer leaflet of the cell membrane — proteins that physically hold neurons together and guide the growth of axons and dendrites. NEGR1 controls three critical aspects of neural architecture: neuronal outgrowth³³ neuronal outgrowth
The extension of axons and dendrites as neurons establish their long-range connections during development and maintain structural plasticity in adulthood, dendritic arborization, and synaptogenesis⁴⁴ synaptogenesis
The formation of synapses — the junctions where two neurons communicate. Reduced synaptogenesis leads to fewer and weaker connections, which is a hallmark of depression at the cellular level.

In the hippocampus — the brain region most responsible for emotional memory, stress regulation, and adult neurogenesis — NEGR1 deficiency has striking consequences. In Noh et al. 2019⁵⁵ Noh et al. 2019
Noh K et al. Negr1 controls adult hippocampal neurogenesis and affective behaviors. Molecular Psychiatry, 2019, mice without NEGR1 showed severely impaired long-term potentiation⁶⁶ long-term potentiation
LTP — the cellular basis of learning and memory, where repeated stimulation strengthens synaptic connections. LTP impairment in the dentate gyrus is strongly associated with depression-like states in animal models (LTP) in the dentate gyrus, sharply reduced adult neurogenesis, and depression/anxiety-like behaviors in validated behavioral assays. The mechanistic pathway involves the interaction of NEGR1 with the LIFR-Lcn2 axis⁷⁷ LIFR-Lcn2 axis
NEGR1 binds to leukemia inhibitory factor receptor (LIFR), which triggers production of Lipocalin-2 (Lcn2). Lcn2 is essential for hippocampal neurogenesis and mood regulation — restoring Lcn2 expression in NEGR1-knockout mice reverses the behavioral and neurogenic deficits: NEGR1 activates the LIFR receptor, which drives Lcn2 expression, which in turn is required for normal hippocampal cell growth.

Beyond the hippocampus, NEGR1 is expressed in hypothalamic circuits regulating both mood and feeding behavior. A 2022 study by Kaare et al.⁸⁸ Kaare et al.
Kaare M et al. Depression-Associated Negr1 Gene-Deficiency Induces Alterations in the Monoaminergic Neurotransmission Enhancing Time-Dependent Sensitization to Amphetamine in Male Mice. Brain Sciences, 2022 demonstrated that NEGR1-deficient mice show altered signaling across all three monoamine systems: elevated striatal dopamine release, higher hippocampal serotonin levels, and dysregulated norepinephrine responses. Significantly, escitalopram treatment rescued reduced hippocampal volume in these animals — suggesting the SSRI's therapeutic effect partly operates through the NEGR1-related neurogenic pathway.

The Evidence

The NEGR1 locus first reached genome-wide significance for depression in the landmark Hyde et al. 2016⁹⁹ Hyde et al. 2016
Hyde CL et al. Identification of 15 genetic loci associated with risk of major depression in individuals of European descent. Nature Genetics, 2016 study using 23andMe data (N=307,354), which identified rs11209948 as the lead NEGR1 SNP. This finding was independently confirmed in the Levey et al. 2021¹⁰¹⁰ Levey et al. 2021
Levey DF et al. Bi-ancestral depression GWAS in the Million Veteran Program and meta-analysis in >1.2 million individuals highlight new therapeutic directions. Nature Neuroscience, 2021 mega-analysis (N=1,154,267), which identified the NEGR1 lead variant rs7531118 at p=8.9×10⁻²⁹ and characterized it as a brain eQTL¹¹¹¹ brain eQTL
A genetic variant that acts as an expression quantitative trait locus — meaning it statistically predicts the expression level of NEGR1 in brain tissue. The Levey study found this effect specifically in the hypothalamus, linking the GWAS signal to reduced NEGR1 expression in a depression-relevant brain region for NEGR1 expression in the hypothalamus.

Integrative analysis by Wang et al. 2020¹²¹² Wang et al. 2020
Wang X et al. Integrating genome-wide association study and expression quantitative trait loci data identifies NEGR1 as a causal risk gene of major depression disorder. Journal of Affective Disorders, 2020 linked the GWAS signal to causal NEGR1 expression changes: rs10789336 significantly affected NEGR1 expression in prefrontal cortex (P=5.14×10⁻³) and correlated with methylation at three CpG sites. The same variant was also associated with general cognitive function (P=2.65×10⁻¹²) and educational attainment (P=1.75×10⁻¹⁴), underscoring NEGR1's role in broad neurocognitive function.

The depression-obesity connection was formally quantified by Zhang et al. 2024¹³¹³ Zhang et al. 2024
Zhang H et al. Dissecting shared genetic architecture between depression and body mass index. BMC Medicine, 2024: genetic correlation between MDD and BMI is rg=0.19 (P=4×10⁻²⁶), and NEGR1 emerged as the top shared gene at genome-wide significance. Expression of NEGR1 was significantly lower in brain tissues of individuals with both depression and obesity, concentrated in the nucleus accumbens and anterior cingulate cortex.

Practical Implications

For G-allele carriers, the key leverage points are the NEGR1 gene's two main functions: hippocampal neurogenesis and hypothalamic monoamine organization. Adult hippocampal neurogenesis is one of the few brain processes that responds robustly to behavioral intervention — BDNF (brain-derived neurotrophic factor), the master regulator of neurogenesis, is strongly upregulated by aerobic exercise and certain dietary compounds. Given that the NEGR1-Lcn2 pathway is itself pro-neurogenic, G-allele carriers have a biologically motivated reason to prioritize neurogenesis-supporting interventions. The monoaminergic dysregulation observed in NEGR1-deficient animals also explains the clinical observation that SSRI treatment appears effective in carriers — escitalopram rescued hippocampal volume in animal models through pathways overlapping the NEGR1 circuit.

The dual mood-metabolic nature of NEGR1 means that interventions that simultaneously support neurogenesis and metabolic health (such as dietary protein adequacy and omega-3 intake) may be particularly relevant for G-allele carriers compared to the general population.

Interactions

NEGR1 variants interact with BDNF (rs6265): since NEGR1 drives hippocampal neurogenesis through the LIFR-Lcn2 axis, and BDNF is the master neurogenic signal, carriers of both risk alleles (NEGR1 G and BDNF Met/Met) face compounded impairment of hippocampal neuroplasticity. This combination would benefit most from consistent aerobic exercise, the most reliably effective way to upregulate BDNF and hippocampal neurogenesis simultaneously.

COMT (rs4680) represents a relevant monoaminergic interaction: the Kaare et al. 2022 data showing dysregulated dopamine and norepinephrine in NEGR1-deficient animals suggests that slow COMT (Met/Met) individuals who also carry the NEGR1 G allele may have compounded monoamine signaling abnormalities, particularly under stress. This combination warrants attention to stress-triggered mood episodes.