Whether MTHFR deficiency has any effect at all on all-cause mortality is unclear. One Dutch study showed that the MTHFR mutation was more prevalent in younger individuals (36% relative to 30%), and found that elderly men with MTHFR had an elevated mortality rate, attributable to cancer. Among women, however, no difference in life expectancy was seen. More recently, however, a meta-analysis has shown that overall cancer rates are barely increased with an odds ratio of 1.07, which suggests that an impact on mortality from cancer is small or zero.
Methylenetetrahydrofolate reductase deficiency
Dihydrofolate reductase deficiency
Adenine phosphoribosyltransferase deficiency
Guanidinoacetate methyltransferase deficiency
5,10-methenyltetrahydrofolate synthetase deficiency
Purine nucleoside phosphorylase deficiency
Dihydropyrimidine dehydrogenase deficiency
Adenosine deaminase 2 deficiency