Kashyap V K, Guha Saurav, Sitalaximi T, Bindu G Hima, Hasnain Seyed E, Trivedi R
National DNA Analysis Centre, Central Forensic Science Laboratory, 30 Gorachand Road, Kolkata 700014, West Bengal, India.
BMC Genet. 2006 May 17;7:28. doi: 10.1186/1471-2156-7-28.
Indian populations endowed with unparalleled genetic complexity have received a great deal of attention from scientists world over. However, the fundamental question over their ancestry, whether they are all genetically similar or do exhibit differences attributable to ethnicity, language, geography or socio-cultural affiliation is still unresolved. In order to decipher their underlying genetic structure, we undertook a study on 3522 individuals belonging to 54 endogamous Indian populations representing all major ethnic, linguistic and geographic groups and assessed the genetic variation using autosomal microsatellite markers.
The distribution of the most frequent allele was uniform across populations, revealing an underlying genetic similarity. Patterns of allele distribution suggestive of ethnic or geographic propinquity were discernible only in a few of the populations and was not applicable to the entire dataset while a number of the populations exhibited distinct identities evident from the occurrence of unique alleles in them. Genetic substructuring was detected among populations originating from northeastern and southern India reflective of their migrational histories and genetic isolation respectively.
Our analyses based on autosomal microsatellite markers detected no evidence of general clustering of population groups based on ethnic, linguistic, geographic or socio-cultural affiliations. The existence of substructuring in populations from northeastern and southern India has notable implications for population genetic studies and forensic databases where broad grouping of populations based on such affiliations are frequently employed.
拥有无与伦比遗传复杂性的印度人群受到了世界各地科学家的广泛关注。然而，关于他们的祖先这一基本问题，即他们在基因上是否都相似，还是确实存在因种族、语言、地理或社会文化归属而产生的差异，仍未得到解决。为了解开其潜在的遗传结构，我们对代表所有主要种族、语言和地理群体的54个印度内婚制群体的3522名个体进行了研究，并使用常染色体微卫星标记评估了遗传变异。
最常见等位基因的分布在各群体中是均匀的，揭示了潜在的遗传相似性。仅在少数群体中可辨别出暗示种族或地理邻近性的等位基因分布模式，且不适用于整个数据集，而许多群体因其独特等位基因的出现而呈现出明显的特征。在分别源自印度东北部和南部的群体中检测到了遗传亚结构，这分别反映了它们的迁徙历史和遗传隔离。
我们基于常染色体微卫星标记的分析未发现基于种族、语言、地理或社会文化归属的群体普遍聚类的证据。印度东北部和南部群体中存在亚结构，这对群体遗传学研究和法医数据库具有显著意义，因为在这些研究和数据库中经常根据此类归属对群体进行广泛分组。
