What is differential gene expression analysis?

Differential gene expression analysis is a process used to compare the expression levels of genes between different biological samples or conditions. It involves analyzing normalized read count data to identify statistical differences in gene expression levels between these groups. As an example, one can compare the expression levels of each gene between Group A and Group B to identify any statistically significant differences. If Gene Z for instance shows higher expression in Group A compared to Group B with a p-value below a specified threshold (e.g., p < 0.05), it would indicate Gene z to be differentially expressed between the two groups.Similarly, if Gene Z exhibits lower expression in Group A compared to Group B with a significant p-value, it would also be considered differentially expressed.