Doctor’s Data, Inc. has served healthcare practitioners from its CLIA-licensed laboratory in St. Charles, Illinois, since 1972. Best known as a pioneer in essential and toxic elemental testing, the laboratory also developed functional biochemical panels that sit alongside genetics rather than replacing them. The Plasma Methylation Profile is one of those tools: it measures the live metabolites of methionine metabolism so you can see how methylation and transsulfuration are actually performing, not only which SNPs are present. Normal methionine metabolism is required for the methylation of DNA, RNA, proteins, phospholipids, and neurotransmitters, and for the downstream synthesis of cysteine, sulfate, taurine, and glutathione. Problems can appear at any age and are commonly driven by nutrient cofactor gaps (folate, B12, B6, betaine, magnesium), ageing, liver function, and toxicant exposure — lead, for example, can impair MTHFR-dependent remethylation. Genotyping (MTHFR, MS/MTR, CBS and others) shows predisposition. This plasma profile shows phenotypic expression and is therefore useful both at baseline and for guiding and monitoring nutritional support. The panel reports methionine, SAM (S-adenosylmethionine), SAH (S-adenosylhomocysteine), the SAM: SAH methylation index, homocysteine, cystathionine and cysteine. SAM is the principal methyl donor. SAH is the product of every SAM-dependent methylation reaction and a potent inhibitor of those same enzymes, so it must be cleared efficiently. A low SAM:SAH ratio is a sensitive marker of under-methylation; Doctor’s Data interprets a ratio above 4 as more favourable methylation potential. Elevated homocysteine is an independent cardiovascular risk factor; elevated SAH may be an even stronger vascular-risk signal. The transsulfuration arm (homocysteine → cystathionine → cysteine) indicates whether homocysteine is being diverted toward glutathione synthesis rather than recycling back to methionine. Clinically, the profile is used when methylation or detoxification capacity is in question — cardiovascular risk, mood and psychiatric presentations, neurodegenerative disease, immune dysregulation, impaired metal or xenobiotic clearance, reproductive and congenital risk work-ups, autism spectrum assessment, and unexplained fatigue or nutrient-responsive illness. Results can direct targeted support (methylfolate, methylcobalamin or hydroxocobalamin, B6/P5P, betaine/TMG, riboflavin, magnesium) and help you avoid over-methylating a patient whose block is downstream. Test specifications Methylation Profile: plasma Sample type: Fasting plasma (EDTA draw; centrifuge within 15 minutes; freeze within 45 minutes). Overnight fast. Stop methionine, cysteine and SAMe-containing supplements for 48 hours unless you direct otherwise. Key markers: Methionine; S-adenosylmethionine (SAM); S-adenosylhomocysteine (SAH); SAM:SAH ratio (methylation index); homocysteine; cystathionine; cysteine Turanround Time: 2-3 WeeksSample Report
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