Аннотация:Polyunsaturated fatty acids (PUFAs) cascades include the metabolism of w-3/ w-6 acids, i.e. elongation and desaturation processes, transport, degradation, as well as synthesis of oxylipins via the lipoxygenase (LOX), cyclooxygenase (COX), and epoxygenase (CYP) branches of transformation into prostaglandins, leukotrienes and other compounds acting through nuclear and membrane receptors. PUFAs and oxylipins are active participants of inflammatory processes and therefore they are under intensive investigations associated with the study of the systemic disorders biology, including neurodegenerative diseases. The aim of this work is to evaluate changes in the expression of PUFAs cascades genes in various tissues of patients with neurodegenerative diseases. Datasets were taken from GEO and PDBP databases. We analysed the following datasets: GSE135036 (Parkinson’s disease); GSE138614 (multiple sclerosis); GSE125583 (Alzheimer’s disease); GSE124439 (amyotrophic lateral sclerosis). Salmon software (v1.0.0) was used for wicked-fast transcript quantification from RNA-seq data. The expression was summarized at the gene and transcript levels using R tximport. All available metadata about patients is included in the design as covariates. When evaluating a differential expression, 2 boundaries of the adjusted value of the pplotDispEsts significance level (0.05 and 0.01) were selected. When studying the distribution of gene expression by autosomes and X chromosome, the Core preprocessor package R for quantum normalization and the Kolmogorov- Smirnov pair test was used to test the differences between samples with high and low XIST gene expression. The involvement of PUFAs cascade genes in the inflammatory processes accompanying studied diseases was estimated. The dependence of expression parameters and patients clinical data is discussed. This study was supported by the RFBR research project № 19-29-01243.