Allele-specific expression

Many other applications have been carried out using semi-quantitative primer extension based MALDI-TOF MS analysis with unknown analyte concentrations. One example involves the quantification of differential allele-specific expression. Medelian inheritance of allele-specific expression has been shown in humans (40). Allele-specific expression is of great importance for the identification of genetic components, which lead to population... 

An effective and elegantly uncomplicated method for directly assessing allele-specific transcript abundance within a normal chromosomal context has been used by several groups (22,23,25) to examine allele-specific expression in human samples. Cowles et al. (26) have used this method to examine such variation between mouse strains. These groups use SNPs in the transcribed regions of genes as tools to measure allele-specific expression levels of genes... 

A group led by Lee and Buetow (28) describes an efficient approach to EAI analysis that uses Affymetrix HuSNP chips to assay for both sample genotype and allele-specific expression level. Of 602 informative (heterozygous) genes expressed in kidney or liver, 54% were found to show EAI in at least one of seven individuals tested. 

Ronald, J., Akey, J.M., Whittle, J., Smith, E.N., Yvert, G., and Kruglyak, L. 2005. Simultaneous genotyping, gene expression measurement, and detection of allele-specific expression with oligonucleotide arrays. Gen. Res. 15,284-291. 

The analysis of gene differential expression is complicated by the potentially subtle differences associated with alterations in a single allele as well as by variations between individuals that arise from environmental or physiological factors. To circumvent these analytic problems, a method, named allele-specific differential expression analysis, was developed to compare the relative expression levels of two alleles of the same gene within the same cellular sample. The studies of allele-specific expression revealed that differential expression is relatively common in the human population. 

Key Words Allele-specific expression SNP gene chip genotyping genetic variation complex disease. 

Allele-specific expression levels can be assessed in two ways. Expression of mRNA and cDNA with different alleles at heterozygote SNPs is assessed using oligonucleotides and TaqMan/real-time PCR 5 nuclease assays (ABI, Foster City, CA) or the primer extension method (SnapShot, ABI, Foster City, CA and MALDI TOF, Sequenome). 

The basic concept described by Ding et al. has recently been extended to exciting new aspects of gene expression, including the quantitation of allele-specific expression and the quantitative analysis of splice variants [227, 228). 

Knight JC. Allele-specific gene expression uncovered. Trends Genet 2004 20(3) 113-116. 

Assaying Differential Ribosomal RNA Gene Expression with Allele-Specific Probes... 

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