She underwent targeted next generation sequencing panel for renal tubular acidosis for five genes (ATP6VOA4, ATP6V1B1, CA2, SLC4A1, SLAC4A4) and 21 additional genes were added which were known to cause Fanconi syndrome (ALDOB, ATP7B, BCS1L, CLCN5, CTNS, EHHADH, FAH, G6PC, GALT, GATM, HNF1A, HNF4A, LRP2, NDUFAF6, OCRL, SLC2A2, SLC34A1, SLC3A1, SLC7A7, SLC7A9, VPS33B). The gene discussed is CTNS; the disease is Fanconi renotubular syndrome.