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. 2014 Jun;26(3):165-70.
doi: 10.3969/j.issn.1002-0829.2014.03.009.

Use of diplotypes - matched haplotype pairs from homologous chromosomes - in gene-disease association studies

Lingjun Zuo  1 , Kesheng Wang  2 , Xingguang Luo  1
Affiliations

Use of diplotypes - matched haplotype pairs from homologous chromosomes - in gene-disease association studies

Lingjun Zuo et al. Shanghai Arch Psychiatry. 2014 Jun.

Abstract
in English, Chinese

Alleles, genotypes and haplotypes (combinations of alleles) have been widely used in gene-disease association studies. More recently, association studies using diplotypes (haplotype pairs on homologous chromosomes) have become increasingly common. This article reviews the rationale of the four types of association analyses and discusses the situations in which diplotype-based analyses are more powerful than the other types of association analyses. Haplotype-based association analyses are more powerful than allele-based association analyses, and diplotype-based association analyses are more powerful than genotype-based analyses. In circumstances where there are no interaction effects between markers and where the criteria for Hardy-Weinberg Equilibrium (HWE) are met, the larger sample size and smaller degrees of freedom of allele-based and haplotype-based association analyses make them more powerful than genotype-based and diplotype-based association analyses, respectively. However, under certain circumstances diplotype-based analyses are more powerful than haplotype-based analysis.

等位基因，基因型和单体型（等位基因组合）已被广泛应用于基因-疾病的关联研究。最近，使用双体型（同源染色体单体型对）的关联研究已经越来越普遍。本文综述了四种关联分析类型的基本原理，并探讨了为什么以双体型为基础的关联分析比其他类型的关联分析更高效。单体型关联分析比基于等位基因的关联分析更高效，以双体型为基础的关联分析比基于基因型的关联分析更高效。在标记之间没有交互作用并且符合Hardy-Weinberg平衡（HWE）标准的情况下，以等位基因和单体型为基础的关联分析样本量较大、自由度较小，使它们分别比基因型和双体型为基础的关联分析更高效。然而，在某些情况下以双体型为基础的关联分析比单体型关联分析更高效。

Keywords: Hardy-Weinberg equilibrium; association analysis; diplotype; genotypes; haplotype; interaction effects.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1.
Figure 1.. Model of alleles, genotypes, haplotypes and diplotypes on a pair of chromosomes
See this image and copyright information in PMC

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