Departament de Ciències de la Salut i de la Vida, Institut de Biologia Evolutiva (CSIC-UPF), Universitat Pompeu Fabra, 08003 Barcelona, Spain.
Hum Genet. 2012 Aug;131(8):1305-17. doi: 10.1007/s00439-012-1157-3. Epub 2012 Mar 11.
African Pygmies are hunter-gatherer populations from the equatorial rainforest that present the lowest height averages among humans. The biological basis and the putative adaptive role of the short stature of Pygmy populations has been one of the most intriguing topics for human biologists in the last century, which still remains elusive. Worldwide convergent evolution of the Pygmy size suggests the presence of strong selective pressures on the phenotype. We developed a novel approach to survey the genetic architecture of phenotypes and applied it to study the genomic covariation between allele frequencies and height measurements among Pygmy and non-Pygmy populations. Among the regions that were most associated with the phenotype, we identified a significant excess of genes with pivotal roles in bone homeostasis, such as PPPT3B and the height associated SUPT3H-RUNX2. We hypothesize that skeletal remodeling could be a key biological process underlying the Pygmy phenotype. In addition, we showed that these regions have most likely evolved under positive selection. These results constitute the first genetic hint of adaptive evolution in the African Pygmy phenotype, which is consistent with the independent emergence of the Pygmy height in other continents with similar environments.
非洲俾格米人是来自赤道雨林的狩猎采集人群，他们的平均身高是人类中最低的。在过去的一个世纪里，俾格米人群矮小的生物学基础和潜在的适应角色一直是人类生物学家最感兴趣的话题之一，但至今仍未得到解答。全世界俾格米人的体型趋同进化表明，表型受到强烈的选择压力。我们开发了一种新的方法来研究表型的遗传结构，并将其应用于研究俾格米人和非俾格米人群之间等位基因频率与身高测量之间的基因组共变。在与表型最相关的区域中，我们鉴定到了大量与骨稳态相关的关键基因，如 PPPT3B 和与身高相关的 SUPT3H-RUNX2。我们假设骨骼重塑可能是俾格米表型的关键生物学过程。此外，我们还表明，这些区域很可能是在正选择下进化而来的。这些结果首次为非洲俾格米表型的适应性进化提供了遗传线索，这与其他具有相似环境的大陆中独立出现的俾格米身高是一致的。
