Overview
The LEPR gene encodes the leptin receptor, which is essential in the hypothalamus for the feeling of satiety and energy balance. Leptin is produced by fat cells and signals the energy storage level to the brain via LEPR.
📍 Position
1p31.3 (Chromosome 1)
1p31.3 (Chromosome 1)
🏷️ Category
Metabolism
Metabolism
⚡ Receptor Type
Cytokine Receptor Superfamily
Cytokine Receptor Superfamily
📊 Frequency
Arg-allele ~40-55%
Arg-allele ~40-55%
The Leptin Signaling Pathway
Leptin is the central hormone of energy homeostasis:
Adipose Tissue
Leptin Production
Leptin Production
→
Blood
Leptin Level ↑
Leptin Level ↑
→
Hypothalamus
LEPR Activated
LEPR Activated
→
Satiety
Appetite ↓, Energy Expenditure ↑
Appetite ↓, Energy Expenditure ↑
💡 The “Satiety Hormone”: Paradoxically, obese individuals often have elevated leptin levels (leptin resistance), but the receptor responds poorly. This is comparable to insulin resistance in diabetes.
🧬 Genetic Variant
rs1137101 (Q223R)
1:66529967
1:66529967
Gln (Better)
G
/
Arg (Risk)
A
Q223R (Gln223Arg): The A-variant (Arginine) shows reduced leptin signaling. This leads to a slightly higher BMI and higher leptin levels.
G/G (Gln/Gln)
Normal receptor function. Better satiety signaling.
Normal receptor function. Better satiety signaling.
A/A or A/G (Arg Carriers)
~0.5-1 kg/m² higher BMI. Slightly reduced satiety signals.
~0.5-1 kg/m² higher BMI. Slightly reduced satiety signals.
⚠️ Rare Mutations: There are also rare loss-of-function mutations in the LEPR gene. Those affected suffer from massive, insatiable hunger pangs and extreme obesity starting in early childhood (congenital leptin receptor deficiency).
🍽️ Appetite Regulation & Obesity
G/G (Normal Function)
- Normal sense of satiety
- Effective energy balance
- Leptin signals are processed efficiently
- Easier weight management
With A-Allele (Reduced Function)
- Delayed sense of satiety
- Tendency toward larger portion sizes
- Higher leptin levels (compensation)
- Slightly increased risk of obesity
✅ Lifestyle Recommendations
For A-Allele Carriers (mild impairment):
- Eat slowly: Give delayed satiety signals time to reach the brain (~20 minutes)
- High-volume, low-calorie foods: Vegetables, salads, the Volumetrics principle
- Protein-rich meals: Protein promotes satiety via other mechanisms
- Regular meals: Avoids extreme hunger spikes
- Adequate sleep: Lack of sleep lowers leptin and increases ghrelin
💡 Important: Even with an unfavorable LEPR genotype, obesity is preventable! Genetic predisposition only shifts the balance slightly—lifestyle remains decisive. Genetics is never destiny!
📚 Data Sources
- OMIM: #601007 (LEPR Gene)
- dbSNP: rs1137101
- PubMed: Clement et al. (1998) – A mutation in the human leptin receptor gene
- Nature: Farooqi et al. – Clinical spectrum of obesity and mutations in LEPR
- Obesity Reviews: Q223R polymorphism and obesity risk
Last Update: February 2026
Biological Function
Leptin is produced by fat cells and signals the brain (hypothalamus) via the LEPR receptor about energy stores. The Q223R variant (rs1137101) influences signal transmission: The Arg-allele (A) shows weaker signals, which can lead to slightly increased appetite and weight. Rare Loss-of-Function mutations cause severe monogenic obesity with insatiable hunger.
Associated Conditions
Obesity
Insulin Resistance
Metabolic Syndrome
Congenital Leptin Receptor Deficiency (rare, severe childhood obesity)
Molecular Analysis
Analyzed Markers
rs1137101
Risk Factor
Pos: 1:66529967 |
Alleles: G/A
Q223R (c.668G>A) - A-allele (Arg) associated with reduced leptin signaling, slightly increased BMI (0.5-1 kg/m²), higher leptin levels. G-allele (Gln): better receptor function.