so here is an example from one of the trait sites and this one is correct
0%
You tend to have a higher level of folate in blood serum
0%
You tend to have an intermediate level of folate in blood serum
100%
You tend to have a lower level of folate in blood serum
Reference papers and your DNA
Genome-wide association study of vitamin B6, vitamin B12, folate, and homocysteine blood concentrations.
Tanaka T et al. 2009
To investigate genetic factors that affect circulating vitamin B6, vitamin B12, folate and homocysteine, a genome-wide association meta-analysis was conducted in large samples from three cohorts: InCHIANTI, SardiNIA and BLSA. The top loci were replicated in an independent sample from the Progetto Nutrizione study. For folate concentration, the most significant SNP is located ~100 kb from MTHFR and the second SNP is in the 30 untranslated region of the prickle-like homolog 2 gene, PRICKLE2.
www.ncbi.nlm.nih.gov/pubmed/19303062
here is an example of 23andme
for this they used a statistical model and a curated model
They showed me the variants. Put them in circles..the bigger the circle the bigger the effect. Biggest circle was on Chromosome 19
they determined I favored Salty snacks..and I do
“Genetics
Like almost all traits, taste preference is partly shaped by genetics, and partly by environment. 23andMe research identified 43 genetic markers where people can have variants that make them more likely to prefer sweet snacks or salty/savory snacks. A few of these 43 genetic markers are in or near genes involved in brain development or function (like CDH8, ELAVL2, AUTS2, and KCNA3). But most are near genes with a broad range of functions, perhaps reflecting the complexity of this trait.”