ETFB and multiple acyl-CoA dehydrogenase deficiency: MADD is known to be caused by variants in ETFA, ETFB, and ETFDH, though in recent years the riboflavin transporter genes and mitochondrial FAD transporter gene have also been associated with MADD‐like phenotype (Bosch et al., 2011; Schiff et al., 2016).