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Relatives have more similar gut microbiomes than nonrelatives, but the degree to which this similarity results from shared genotypes versus shared environments has been controversial. Here, we leveraged 16,234 gut microbiome profiles, collected over 14 years from 585 wild baboons, to reveal that host genetic effects on the gut microbiome are nearly universal. Controlling for diet, age, and socioecological variation, 97% of microbiome phenotypes were significantly heritable, including several reported as heritable in humans. Heritability was typically low (mean = 0.068) but was systematically greater in the dry season, with low diet diversity, and in older hosts. We show that longitudinal profiles and large sample sizes are crucial to quantifying microbiome heritability, and indicate scope for selection on microbiome characteristics as a host phenotype.
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Prioritizing host phenotype to understand microbiome heritability in plants
Summary Breeders and evolutionary geneticists have grappled with the complexity of the ‘genotype‐to‐phenotype map’ for decades. Now, recent studies highlight the relevance of this concept for understanding heritability of plant microbiomes. Because host phenotype is a more proximate cause of microbiome variation than host genotype, microbiome heritability varies across plant anatomy and development. Fine‐scale variation of plant traits within organs suggests that the well‐established concept of ‘microbiome compartment’ should be refined. Additionally, recent work shows that the balance of deterministic processes (including host genetic effects) vs stochastic processes also varies over time and space. Together, these findings suggest that re‐centering plant phenotype – both as a predictor and a readout of microbiome function – will accelerate new insights into microbiome heritability.
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- PAR ID:
- 10446524
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 232
- Issue:
- 2
- ISSN:
- 0028-646X
- Format(s):
- Medium: X Size: p. 502-509
- Size(s):
- p. 502-509
- Sponsoring Org:
- National Science Foundation
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