Costas Javier, Salas Antonio, Phillips Christopher, Carracedo Angel
Centro Nacional de Genotipado, Fundación Pública Galega de Medicina Xenómica, Hospital Clínico Universitario, Universidade de Santiago de Compostela, E15706, Santiago de Compostela, Spain.
Gene. 2005 Apr 11;349:219-25. doi: 10.1016/j.gene.2004.12.042.
An important proportion of the human genome is organized in regions of high linkage disequilibrium (LD) and low haplotype diversity, referred to as haplotype blocks. Here, we perform a genome-wide screen of haplotype-like blocks presenting just two main haplotypes at a frequency higher than 1%, based on single-nucleotide polymorphism (SNP) frequencies from two populations: African-Americans and Caucasians, using data from the Celera SNP database. These haplotype-like blocks of reduced diversity are more abundant and of longer size in Caucasians, in agreement with population history. Several of the discovered blocks are good candidates for targets of natural selection, such as those blocks containing a cluster of bitter taste receptors or the apolipoprotein L1. In addition, several genes putatively involved in susceptibility to common diseases are included in these haplotype-like blocks of reduced diversity. This fact may present important implications in association studies, leading to a reduction of genotyping efforts.
人类基因组的一个重要部分由高连锁不平衡（LD）和低单倍型多样性区域组成，这些区域被称为单倍型块。在此，我们基于来自非洲裔美国人与高加索人这两个人群的单核苷酸多态性（SNP）频率，利用塞雷拉SNP数据库的数据，对呈现两种主要单倍型且频率高于1%的类单倍型块进行全基因组筛选。与群体历史一致，这些多样性降低的类单倍型块在高加索人中更为丰富且长度更长。一些发现的块是自然选择靶点的良好候选者，例如那些包含一组苦味受体或载脂蛋白L1的块。此外，这些多样性降低的类单倍型块中包含了几个推测与常见疾病易感性相关的基因。这一事实可能在关联研究中具有重要意义，从而减少基因分型工作。
