Allelic imbalance metre ( A llim), a new tool for measuring allele‐specific gene expression with RNA ‐seq data

Estimating differences in gene expression among alleles is of high interest for many areas in biology and medicine. Here, we present a user‐friendly software tool, A llim, to estimate allele‐specific gene expression. Because mapping bias is a major problem for reliable estimates of allele‐specific gene expression using RNA ‐seq, A llim combines two different strategies to account for the mapping biases. In order to reduce the mapping bias, A llim first generates a polymorphism‐aware reference genome that accounts for the sequence variation between the alleles. Then, a sequence‐specific simulation tool estimates the residual mapping bias. Statistical tests for allelic imbalance are provided that can be used with the bias corrected RNA ‐seq data.