Rajalingam Raja, Du Zeying, Meenagh Ashley, Luo Lihui, Kavitha Valampuri John, Pavithra-Arulvani Rajamanickam, Vidhyalakshmi Arumugam, Sharma Surendra K, Balazs Ivan, Reed Elaine F, Pitchappan Ramasamy M, Middleton Derek
UCLA Immunogenetics Center, Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, University of California at Los Angeles, Los Angeles, CA 90095, USA.
Immunogenetics. 2008 May;60(5):207-17. doi: 10.1007/s00251-008-0286-2. Epub 2008 Mar 28.
By interacting with polymorphic HLA class I molecules, the killer cell immunoglobulin-like receptors (KIR) influence the innate and adaptive immune response to infection. The KIR family varies in gene content and sequence polymorphism, thereby, distinguishing individuals and populations. To investigate KIR diversity in the earliest settlers of India, we have characterized the KIR gene content in three Dravidian-speaking populations (Mollukurumba, Kanikar, and Paravar) from the state of Tamil Nadu, southern India. The activating KIR genes and putative group-B KIR haplotypes were frequent in Paravar and Kanikar, a scenario analogous to those seen previously in other populations of Indian origin, indicating that predominance of group-B KIR haplotypes is the characteristic feature of Indian populations. In contrast, the KIR gene profile of Mollukurumba was more related to Caucasian type. It is not clear whether a local-specific selection or a recent admixture from Iran is responsible for such discrete profile in Mollukurumba. Each southern Indian population had distinct KIR genotype profile. Comparative analyses with world populations revealed that group-B KIR haplotypes were frequent in the natives of India, Australia, and America, the populations associated with those involved in extensive prehistoric human migrations. Whether or not natural selection has acted to enrich group-B KIR haplotypes in these migratory descendants is an issue that requires objective testing.
通过与多态性的HLA I类分子相互作用,杀伤细胞免疫球蛋白样受体(KIR)影响对感染的先天性和适应性免疫反应。KIR家族在基因含量和序列多态性方面存在差异,从而区分个体和群体。为了研究印度最早定居者中的KIR多样性,我们对来自印度南部泰米尔纳德邦的三个说达罗毗荼语的群体(莫卢库伦巴、卡尼卡尔和帕拉瓦尔)的KIR基因含量进行了特征分析。激活型KIR基因和假定的B组KIR单倍型在帕拉瓦尔和卡尼卡尔中很常见,这一情况与之前在其他印度裔群体中观察到的情况类似,表明B组KIR单倍型的优势是印度群体的特征。相比之下,莫卢库伦巴的KIR基因谱与高加索类型更相关。目前尚不清楚是局部特异性选择还是最近来自伊朗的基因混合导致了莫卢库伦巴这种独特的基因谱。每个印度南部群体都有独特的KIR基因型谱。与世界其他群体的比较分析表明,B组KIR单倍型在印度、澳大利亚和美洲的原住民中很常见,这些群体与参与广泛史前人类迁徙的群体有关。自然选择是否在这些迁徙后代中富集了B组KIR单倍型是一个需要客观检验的问题。