Methylation is a process by which a gene's behavior is altered, but the gene itself isn't changed. It requires Vitamin B12 and Folic Acid to convert nutrients from food to energy. If the process is blocked, through stress, viruses, toxins, etc., Glutathione cannot be created. Glutathione detoxifies the body, among other body processes. Normal methionine metabolism is absolutely critical for folate-dependent transmethylation, and transsulfuration. Abnormal metabolism of methionine can be found in both genders at any age. It is usually associated with genetic or nutritional deficiencies, aging and exposures to environmental toxins. For example, lead can impair methylation via inhibition of the enzyme methylenetetrahydrofolate reductase (MTHFR). Conditions associated with untreated, aberrant methionine metabolism include, but are not limited to: Abnormal neurotransmitter metabolism and psychiatric disorders such as schizophrenia and bipolar disorder Neurodegenerative diseases Autism Dysregulation of nitric acid homeostasis Oxidative stress Global under-methylation, synthesis and repair of DNA Immune dysregulation/autoimmunity Cancer Cardiovascular disease Congenital heart disease and birth defects Impaired endogenous detoxification processes Increased risk for Down syndrome The DDI Methylation profile evaluates the plasma levels of methionine, cysteine, SAM, SAH, Hcy and cystathionine, and provides the important "methylation index," a ratio of SAM to SAH. The test results can appropriately guide nutritional support to improve or normalize methionine metabolism and meliorate or prevent the potential adverse consequences associated with inadequate methylation and transsulfuration capacity. Analytes Reported: Cystathionine, plasma Cysteine, plasma Homocysteine, plasma Methionine, plasma S-adenosylhomocysteine; plasma S-adenosylmethionine; plasma SAM, SAH ratio