A Worldwide Analysis of Beta-Defensin Copy Number Variation Suggests Recent Selection of a High-Expressing DEFB103 Gene Copy in East Asia

作者：Hardwick Robert J; Machado Lee R; Zuccherato Luciana W; Antolinos Suzanne; Xue Yali; Shawa Nyambura; Gilman Robert H; Cabrera Lilia; Berg Douglas E; Tyler Smith Chris; Kelly Paul; Tarazona Santos Eduardo; Hollox Edward J^*

来源：Human Mutation, 2011, 32(7): 743-750.

DOI：10.1002/humu.21491

• CNV
• defensin
• antimicrobial
• influenza
• paralogue ratio test

Beta-defensins are a family of multifunctional genes with roles in defense against pathogens, reproduction, and pigmentation. In humans, six beta-defensin genes are clustered in a repeated region which is copy-number variable (CNV) as a block, with a diploid copy number between 1 and 12. The role in host defense makes the evolutionary history of this CNV particularly interesting, because morbidity due to infectious disease is likely to have been an important selective force in human evolution, and to have varied between geographical locations. Here, we show CNV of the beta-defensin region in chimpanzees, and identify a beta-defensin block in the human lineage that contains rapidly evolving noncoding regulatory sequences. We also show that variation at one of these rapidly evolving sequences affects expression levels and cytokine responsiveness of DEFB103, a key inhibitor of influenza virus fusion at the cell surface. A worldwide analysis of beta-defensin CNV in 67 populations shows an unusually high frequency of high-DEFB103-expressing copies in East Asia, the geographical origin of historical and modern influenza epidemics, possibly as a result of selection for increased resistance to influenza in this region. Hum Mutat 32:743-750, 2011.

• 出版日期2011-7