In this manner, HNF4A-associated FRTS would be related to mitochondriopathies with isolated Fanconi syndrome or Fanconi syndrome as renal manifestation in more widespread disease (Klootwijk et al., 2014, O’Toole, 2014, Reichold et al., 2018). Here, HNF4A is linked to Fanconi renotubular syndrome.