RE: https://disabled.social/@tomkindlon/116417351897995176
This study https://www.tandfonline.com/doi/full/10.1080/17501911.2026.2656361 passes lots of hurdles:
this is one of the few epigenetic studies to analyze persistent genome-wide DNAm in longitudinally matched samples across COVID-19 and Long-COVID phenotypes, including targeted assessment of the contributions of genes on the X chromosome
And some of their findings are encouraging; they found no sign of increased epigenetic pace of aging in pre-COVID loci.
That's no guarantee on that front though; epigenetic clocks may not be causally harmful, there are surely other as-yet unidentified loci, and there may be epigenetic changes at a small set of loci causally tied to Long COVID - remember a single methylation can in some conditions drastically alter expression - but it's quite encouraging.
And I want to be happy and positive about their other findings, but really I'm happiest about the fact they do their job as scientists and point out what you might have guessed:
The Illumina EPIC V2 array interrogates only a small fraction of the estimated 28 million CpG sites in the human genome, and while many of these are in regulatory regions, it is estimated that up to 80% of CpGs are constitutively methylated and may not have any regulatory relevance. Moreover, the methylome is highly correlated within individuals, meaning that subtle or localized changes could be missed in genome-wide analyses
Their estimates of cell-type composition were coarse (only 6 types, no Tn measure) and as expected for that coarseness there's no sign of pathology.
#COVID #COVID19 #SARSCoV2 #CovidIsNotOver