  Individual expression profiles from EBV transformed cell lines are an
emerging resource for genomic investigation. In this study we characterize the
effects of age, sex, and genetic variation on gene expression by surveying
public datasets of such profiles. We establish that the expression space of
cell lines maintains genetic as well as non-germline information, in an
individual-specific and cross-tissue manner. Age of donor is associated with
the expression of 949 genes in the derived cell line. Age-associated genes
include over-representation of immune-related genes, specifically MHC Class I
genes, a phenomenon that replicates across tissues and organisms. Sex
associated genes in these cell lines include likely candidates, such as genes
that escape X-inactivation,testis specific expressed genes, androgen and
estrogen specific genes, but also gene families previously unknown to be sex
associated such as common microRNA targets (MIR-490, V_ARP1_01, MIR-489).
Finally, we report 494 transcripts whose expression levels are associated with
a genetic variant in cis, overlapping and validating previous reports.
Incorporating age in analysis of association facilitates additional discovery
of trans-acting regulatory genetic variants. Our findings promote expression
profiling of transformed cell lines as a vehicle for understanding cellular
systems beyond the specific lines.
