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Worldwide diversity and geographic structure of killer-cell immunoglobulin-like receptor (KIR) gene content

Introduction: Killer-cell immunoglobulin-like receptor (KIR) gene content shapes natural killer-cell responses and varies substantially among populations.

By Fernandez

Score█████░░░░░4.7

Key numbers

  • 53.5% of variation in KIR

Caveats

  • Preprint; not yet peer reviewed.

VerdictWorth a reader's time today.

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Abstract

Introduction: Killer-cell immunoglobulin-like receptor (KIR) gene content shapes natural killer-cell responses and varies substantially among populations. We examined whether worldwide KIR diversity reflects regional structure, isolation by distance, serial founder effects, or latitudinal gradients. Data and methods: Carrier frequencies for 11 variable KIR genes were obtained from the Allele Frequency Net Database. The primary analysis included 189 locally sampled, non-diaspora, non-mixed populations from 70 countries, comprising 25,469 individuals; 161 populations had complete 11-gene profiles. Diversity indices, ordination, clustering, permutation-based variance decomposition, Mantel tests, and regression models were used to characterize geographic structure. Serial founder effects were evaluated using four distance measures from East Africa, both globally and within the Old World. Models of latitude incorporated spatial autocorrelation. Prespecified sensitivity analyses evaluated alternative population sets, gene panels, geographic classifications, weighting schemes, and multivariate outlier exclusion. Results: Geographic region explained 53.5% of variation in KIR profiles, substantially exceeding the permutation-null expectation of 6.9%, although multivariate dispersion differed among regions. Twenty-five of 28 pairwise regional comparisons remained significant after false-discovery-rate correction. Isolation by distance was modest (Mantel r=0.3003) and weakened after controlling for region (r=0.1557). KIR diversity did not decline with distance from East Africa globally but decreased strongly within the Old World (expected heterozygosity {beta}=-0.0066 and standardized gene content {beta}=-0.0789). B-content decreased nominally with absolute latitude, but latitude was collinear with region and the association survived neither spatial modelling nor sensitivity analyses. Regional differentiation remained robust across analytical specifications, whereas the Old World decline was carried by gene content once standard errors were clustered by country. Conclusion: Worldwide KIR gene-content variation shows pronounced regional differentiation, modest isolation by distance, and no independent latitudinal gradient. Diversity declines with distance from East Africa across the Old World, supporting serial founder effects, but not once the Americas and Oceania are included.

A. Obeso Fernandez

The editor's rubric

Heuristic review

DimensionLevelWeightWhat that level means
Leverage██░░░ 210%Reusable within one subfield (a technique, dataset, or protocol a few groups will adopt).
Magnitude███░░ 320%Large gain: roughly 2x, or a clear new state of the art on a hard, unsaturated problem.
Evidence████░ 432%Strong: large scale, preregistered, independently replicated, or a well-powered randomized trial.
Novelty██░░░ 28%A new combination of known ideas.
Trajectory██░░░ 25%Some room to improve with obvious engineering.
Stakes██░░░ 225%Benefits a professional community (practitioners, clinicians, engineers).

Editor’s rationale

Heuristic triage from title and abstract text only, not a reading of the paper. Cues found: gains (outperforms); novelty (discovery); design (multicenter); verification (independent replication); stakes (global scale).

How the score was computed

rank-2026-10-07

Score█████░░░░░4.7

Score = 10 × (80% × adjusted merit / 10 + 10% × attention + 10% × freshness)

Merit
5.7 / 10
Weighted rubric, evidence-gated.
Adjusted merit
4.7 / 10
Shrunk toward the desk prior by editor confidence (40%).
Attention
4%
Citations, upvotes, points, mentions.
Freshness
92%
Half-life decay since publication.
  • Citations1 (reference 20, via semantic-scholar, Oct 12, 2026, 06:17 UTC)

The record

  • Reviewed by heuristic-v6 on Oct 12, 2026, 06:17 UTC. Paper type: empirical.
  • Categories: genetic and genomic medicine
  • BRIEF, No.8 in the Medicine edition of October 12, 2026.