I've been handed RNA-seq data with a lot of associated covariates. This data has been put through the DESeq2 package and as a result normalised the data. One of the transcripts of interest still has non-normal distribution for two genotypes. This is because many of the normalised counts are now clustered around a value of 4.
This is making it tricky to perform statistical tests because in order to perform parametric tests (in this case I want to perform a ANCOVA or multiple linear regression to include the covariates) the data must be normally distributed.
I also don't want to use a non-parametric test because I can't include all the covariates.
Should I just perform parametric tests ignoring this violation or do I have to just perform non-parametric on all my data for a fair comparrison? Or is there another alternative option I am missing?
Thanks in advance