Thus, we evaluated the structure of biological variability and statistical modeling strategies useful for determining differential expression in mRNA-Seq data with true biological replicates.
The clinical samples were used to represent biological variability and possible pre-analytical variability.
However, the derivation of gene expression signatures from multiple, independent studies is hindered by a number of factors including the absence of standard experimental protocols, biological variability, and limited sample sizes.
This confirmed that the majority of biological variability in expression levels was captured in our pools of 25 males.
Further, the existence of significant biological variability in expression levels of many genes between human hearts is widely recognized.
Under this formulation, the biological variability of the expression of a gene is modelled as a quadratic function of its mean expression μ: (2) σ 2 = μ + b μ 2, where as b = 1 r gets small the negative binomial will approach a Poisson.
This allows identifying and controlling for inherent biological variability of gene expression, between individual animals that might not be related to the E-IAA sub-phenotype and allowed us avoiding the possibility for any preferential transcript amplification.
Each experiment is defined by five parameters: the number of genes whose expression is perturbed in the cancer cells, their multiplicative perturbation factor, the number of heterogeneous tumor samples profiled, the number of sources in the Source Panel and the level of biological variability of the expression profiles of the same sources between different cancer patients.
This is an important issue for toxicogenomics, as studies conducted on cell culture populations demonstrate a wide range of biological variability in gene expression measurements for individual cells under both baseline and challenged conditions (Kuang et al. 2004).
Our interest is in the biological variability of gene expression.
c) Biological variability in Msn2 expression between cells.
