Take a look at the actual paper rather than the press release. <a href="http://www.cell.com/cell-systems/pdfExtended/S2405-4712(15)00009-5" rel="nofollow">http://www.cell.com/cell-systems/pdfExtended/S2405-4712(15)0...</a> .<p>From the paper: "Here, we survey variation and dynamics of active regulatory elements genome-wide using longitudinal
samples from human individuals. We applied Assay
of Transposase Accessible Chromatin with sequenc-
ing (ATAC-seq) to map chromatin accessibility in pri-
mary CD4+ T cells isolated from standard blood
draws from 12 healthy volunteers over time, from
cancer patients, and during T-cell activation. Over
4,000 predicted regulatory elements (7.2%) showed
reproducible variation in accessibility between indi-
viduals. Gender was the most significant attributable
source of variation."<p>A sample size of 12 is small, but makes sense since this is a new technique which enables researchers to identify personal variations in accessible chromatin landscape in
human T cells and trace their genetic, epigenetic, and disease associations. In exploratory experimental science of this sort, sample size is not really a relevant measure.<p>But, even with the small sample size, the results were interesting. In particular, this new technique demonstrates that there are significant differences in the genetic structure of the immune system, which appear to be sex linked. That is not a sexist statement, it is a fact.
There were only 12 people in the study, this can't have any statistical significance. The differences they saw could be completely caused by chance.