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 SLC3A1; the disease is renal tubular acidosis.