A technical guide to DNA methylation testing — arrays versus whole-genome bisulfite sequencing versus nanopore, what the raw files look like, how to process them, and how much of the signal is real.
A direct look at blood-chemistry clocks, methylation clocks, and plasma proteins: which markers carry the signal, how to compute biological age from your own lab data, and how much of the number is noise.
A technical read on epigenetic clocks, blood-chemistry clocks, and survey-based 'bio age' calculators: what each one measures, how precise it is, and how to compute one yourself from your own data.
Two different tests share the name methylation testing: genotyping of one-carbon metabolism genes like MTHFR, and direct measurement of DNA methylation across the genome. This explains what each one measures, how to extract the data yourself, and where the interpretation stops.
Two very different assays are sold under the name 'methylation panel': a one-carbon biochemistry blood panel and a DNA methylation assay. Here is what each one measures, which files you get, and how to process them yourself.
There are two products sold as a 'methylation report': an MTHFR-style SNP panel from genotyping data, and a genome-wide DNA methylation array read out as epigenetic clocks. They measure different things, and only one of them is a measurement of your current biology.
DNA age tests read cytosine methylation at a few hundred CpG sites and regress it onto chronological age. Here is how the assay works, which clocks are worth running, what the error bars really are, and how to process the raw data yourself.
A consumer epigenetics kit measures DNA methylation at CpG sites on an array, then feeds those values into a regression model that outputs an age-like number. Here is what the assay does, what the error bars are, and how to work with the raw IDAT files yourself.
Genetic Genie's methylation panel reads about two dozen genotypes out of a consumer array file. This guide shows how to extract and verify those calls yourself, what they can and cannot tell you, and how to measure actual DNA methylation if that is what you were after.
A practical comparison of DNA methylation tests: which array, which clocks, how to get the raw IDATs, and how to process them yourself with sesame and dnaMethyAge. Plus the noise sources that make a single epigenetic age number close to meaningless.
The Sinclair-associated biological age test is a buccal DNA methylation clock. Here is what methylation clocks measure, how noisy they are, and how to get data you can analyze yourself.