Research

Hormonal

Rare and low-frequency coding genetic variants in genes such as MC4R, GIPR, and KSR2 are significantly associated with Body Mass Index (BMI), with effect sizes approximately ten times larger than those of common variants.

Your genetics play a role in your weight, but for most people, common lifestyle factors (diet, activity) are far more impactful than rare genetic mutations. If you have a known high-impact mutation like MC4R p.Tyr35Ter, you may need more aggressive or specialized medical interventions, but for the general population, focusing on energy balance remains the most effective strategy.

StrongSupportsVERY_HIGH confidence
The effect sizes of rare variants are ~10 times larger than those of common variants, with the largest effect observed in carriers of an MC4R mutation introducing a stop codon (p.Tyr35Ter, MAF = 0.01%), who weighed ~7 kg more than non-carriers.
Valérie Turcot et al. · Nature Genetics · 2017

Why this rating

Meta-analysis of 718,734 individuals with array-wide significance thresholds.

Source

Protein-altering variants associated with body mass index implicate pathways that control energy intake and expenditure in obesity

Valérie Turcot et al. · Nature Genetics · 2017

DOI 10.1038/s41588-017-0011-x

Meta-analysis · 125 studiesCited 427×
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DOI resolved against Crossref · corpus check 2026-06-10

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