Linking SNPs to CAG repeat length in Huntington's disease patients

Abstract
To determine long-range linkage between single-nucleotide polymorphisms (SNPs) and the repeat-containing region of a disease-related gene, Liu et al. develop SNP linkage by circularization (SLiC) and lay the groundwork for using allele-specific RNA interference to target insertion or deletion mutations in disease-associated genes. Allele-specific silencing using small interfering RNAs targeting heterozygous single-nucleotide polymorphisms (SNPs) is a promising therapy for human trinucleotide repeat diseases such as Huntington's disease. Linking SNP identities to the two HTT alleles, normal and disease-causing, is a prerequisite for allele-specific RNA interference. Here we describe a method, SNP linkage by circularization (SLiC), to identify linkage between CAG repeat length and nucleotide identity of heterozygous SNPs using Huntington's disease patient peripheral blood samples.