An allele is one of two or more versions of a gene. An individual inherits two alleles for each gene, one from each parent. If the two alleles are the same, the individual is homozygous for that gene. If the alleles are different, the individual is heterozygous.
Urinary MMA is a Superior Test For Detecting B12 Deficiency, and for Good Reason.
The MMA Test Teaches a Lot About Why B12 is So Important for Energy
First Study to Find a Link