It is suggested that genetic factors may contribute partly to the etiologies of MD, as some associations have been reported for polymorphisms related to gene coding for protein involved in inflammation, circulation, and blood vessels, such as interleukin 1A (–889C/T), interleukin 6–572C/G), protein kinase C beta type (1425G/A), matrix metalloproteinase-1 (–1607G/2G), methylenetetrahydrofolate reductase (MTHFR) (C677T), prothrombin (G20210A), and complement factor H [44,45,46,47,48,49,50,51], and genes involved in free-radical processes. Here, MTHFR is linked to Menkes disease.