Not how much fat a person carries, but where — and it turns out "where" splits into two genetically distinct routes, one of which carries substantially more diabetes and heart disease risk than the other. A person can reach the same waist-to-hip ratio by storing too little fat in the hips or too much in the waist, and a landmark study found the two are not equally dangerous.
Solid lines are connections this site curates. Dashed lines mean the two ends share a research paper — worth knowing, and not a claim that one explains the other.
Waist-to-hip ratio (WHR) — waist circumference divided by hip circumference — is a common measure of body fat distribution, sometimes summarised as "apple" versus "pear" body shape. It predicts cardiometabolic disease independently of overall body mass index, and how much of that variation is genetic, and through which biological route, is what the largest study behind this page set out to answer.
Lotta et al. 2018 analysed up to 452,302 UK Biobank participants of European ancestry and found 202 independent genetic variants associated with WHR. The key move was splitting them: some variants raise WHR mainly by reducing gluteofemoral (hip and thigh) fat, others mainly by increasing abdominal (waist) fat. Using DXA body-composition imaging in 18,330 people, the study confirmed the split was real — the hip-associated variants specifically tracked with less gluteofemoral fat, the waist-associated ones with more abdominal fat.
Then, in more than 636,607 people, both genetic scores were tested against actual disease outcomes. Both predicted higher blood pressure and triglycerides, and both predicted higher risk of type 2 diabetes and coronary disease per unit increase in WHR — but not equally. The score for less hip fat carried the larger risk increase for both diabetes (odds ratio 2.54, versus 1.57 for the waist-fat route) and coronary disease (odds ratio 1.76, versus 1.60). Reduced capacity to store fat in the hips and thighs — not simply "more fat" — was the stronger signal.
The finding fits a broader idea in metabolic research: gluteofemoral fat storage acts as a genuinely protective, relatively safe place for the body to keep surplus energy. A person whose body is less able to expand that storage depot for genetic reasons is left storing fat elsewhere — including in and around organs, where it does more metabolic harm. On this reading, a high waist-to-hip ratio driven by poor hip fat storage capacity is not just a cosmetic difference from one driven by excess waist fat; it may reflect a real difference in how the body handles surplus energy.
This page's 145 variants are drawn predominantly from the Lotta study, with additional loci from several further large studies of the same and closely related traits (WHR adjusted for BMI, WHR in physically active people, and trunk fat ratio specifically). The individual contribution of each smaller study is not itemised here; all are catalogued to the same quality standard.
Waist-to-hip ratio is measured directly with a tape measure, not estimated from genotype. It is sometimes used clinically alongside BMI as an indicator of cardiometabolic risk. No genotype from this page enters that assessment; the polygenic scores described here are research tools, not clinical ones.
The distinction this page emphasises — that low-gluteofemoral-fat and high-abdominal-fat routes to the same WHR carry different risk — is a population-level finding from a very large study, not something that tells an individual which route their own body shape came from. The odds ratios quoted are per standard deviation of genetically predicted WHR, a statistical construct, not a personal risk estimate.
What a 23andMe/AncestryDNA export or raw VCF can and can't tell you about Waist-to-Hip Ratio (Body Fat Distribution) comes down to these specific, well-studied positions — not a diagnosis. 145 positions are linked to this page; the ones this page's own text discusses are shown first.
Databases, guidelines and references
No. WHR is measured directly with a tape measure. These variants explain a population-level share of the variation between people and are not used to estimate an individual's measurement or personal risk.
Not according to this page's main study. A high ratio reached mainly through reduced hip/thigh fat storage carried a larger genetic association with diabetes and coronary disease than one reached mainly through increased waist fat, even though both raise the same measured ratio.
The study's proposed explanation is that gluteofemoral (hip/thigh) fat storage is a relatively safe place for the body to keep surplus energy; someone with less capacity to store fat there may end up storing it in more metabolically harmful places instead, including around organs. This is the study's interpretation of its own finding, not an independently proven mechanism.
Up to 452,302 UK Biobank participants for the genetic discovery, 18,330 for the body-composition imaging that confirmed the hip-versus-waist split, and over 636,607 for the disease-outcome analysis.
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