Additionally, we identified individuals with propionic acidemia (N = 4), methylmalonic acidurias (N = 4 MUT-type; N = 1 CblA-type), isolated remethylation disorders (N = 3 MTHFR deficiency), combined remethylation disorder (N = 1 CblC deficiency) and CBS deficiency (N = 1) (Table 1, Figure 2 and Figure 3). The gene discussed is MMAA; the disease is Methylmalonic aciduria.