SNP linkage disequilibrium

Abbreviated SNP linkage disequilibrium profile for efficacy and common adverse events... 

Fig. 3.2 G raph demonstrating the effect of varying linkage disequilibrium (D ) on relative risk. The underlying susceptibility SNP (D = 1.0) yields a relative risk of 2.5 and the marker and susceptibility SNPs have equal frequencies.

More than 50 polymorphisms, three insertions/deletions, and several promoter alterations that modify gene transcription have been described in the ABCBl gene. There are three single-nucleotide polymorphisms (SNPs) that are common in most racial populations and demonstrate strong linkage disequilibrium the synonymous... 

Another widely studied apo A-IV SNP is an A—>T polymorphism at nucleotide 2346 (first base of codon 347), which causes a threonine-to-serine substitution in the protein product.54-55 The A—>T variant at codon 347 occurs at almost double the frequency of the 360G—>T variant with a prevalence of 22% in Caucasian populations.55-56 However, ethnic differences have been described with lower frequencies in African blacks (9.5%) and Hispanic populations (12.9%).53 The 360G— T and 347A—>T genetic variants are in strong linkage disequilibrium and tend not to occur together.55-57... 

An alternative approach to the analysis of individual candidate gene variants is to use as the unit of analysis gene haplotypes instead of single SNPs. This overrides the need of knowledge on the functional consequences of genetic variants. Several studies of linkage disequilibrium across the human genome have shown that most... 

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