Data acquisition and preprocessing A Novel Computational Approach to Assess Housekeeping Genes Expression Profiling from a Sex Perspective M. Guaita Céspedes1, R. Grillo-Risco1,2, P. Malmierca-Merlo 1,3, D. J Burks 4, A. Galán Albiñana 4, F. García-García 1,2 1 UBB-CIPF, 2. ELIXIR-Spain (INB, ELIXIR-ES), 3 ARI-ATOS SPAIN, 4. MOLECULAR NEUROENDOCRINOLOGY-CIPF Introduction & Aim Housekeeping genes are involved in the maintenance of basic cell functions and are used as calibration tools in gene expression studies. Their proper selection and validation in the particular studied conditions are key for the validity of the obtained results. In this study, we assess the expression profiles of six classical housekeeping genes and different collections of genes covered in the microarray transcriptomic data available at Gene Expression Omnibus database (GEO), to evaluate the stability of their expression in adipose tissue of human and mouse samples, taking into consideration the sex biological variable. Methods Coefficient of Variation IQR/median MAD/median Meta ranking of variability by Rank Products Results References, Acknowledgements and Funding Conclusions 1. Eisenberg, E., & Levanon, E. Y. (2013). Human housekeeping genes, revisited. Trends in Genetics, Vol. 29, pp. 569–574. 2. De Jonge et.al. (2007). Evidence based selection of housekeeping genes. PLoS ONE, 2(9). 3. Caracausi, M., et al.(2017). Systematic identification of human housekeeping genes possibly useful as references in gene expression studies. Molecular Medicine Reports, 16(3), 2397–2410. ●Not all the housekeeping genes proposed in the literature can be used as a reference for both men and women, due to the sex- specific expression patterns. It could be appropriate to consider common reference genes suitable to both sexes. ●This approach allowed us to validate classical housekeeping genes that can be used when comparing both sexes (RPL19, PPIA and UBC), and we propose other genes that can also be used as a reference, such as RPS8, RPS18 and UBB. ●There is a need of including both sexes in the experimental designs of biomedical studies as it would make extensible to the whole population the knowledge generated. It would be interesting to incorporate the sex as an attribute in the sample records of public repositories. Systematic review and selection of the studies Figure 1. PRISMA diagram of the systematic review. Meta-analysis Proposed candidate genes Gene Relative stability Men Relative stability Women Expression levels (TPM) RPS8 194,67 178,33 952,191 RPS18 119,33 296,33 3.173,82 UBB 228 79 252,293 ANXA 396,67 8.968 283,997 DDX39 68 6.633,67 197,455 PLIN4 584,33 11.594,67 499,806 DNASE2 9.911,33 349,33 38,042 NDUFB11 6.168 412,67 144,795 RARA 8.267,67 306 42,575 Systematic review and selection of studies 1 2 Statistical analysis of variability 3 Meta-analysis 4 Selection of common and sex-specific highly expressed and highly stable genes Selection of alternative reference genes 5 qPCR in human and mouse samples Experimental validation 6 Figure 2. Ranking of stability for the housekeeping genes evaluated in human and mouse (A), and men and women (B). Table 1. Potential common and sex-specific reference genes. A) B)