A case report on ATP6V0A4 gene mutation: Forecast of familial deafness by genetic investigation in a patient with autosomal recessive distal renal tubular acidosis

The autosomal recessive form of distal renal tubular acidosis (dRTA), a condition associated with the systemic accumulation of acid owing to its reduced elimination through kidneys, is caused by ATP6V0A4 mutation, which is typically related to either late-onset sensorineural hearing loss (SNHL) or normal hearing. This article reports dRTA in seven year old boy, born to a Chinese couple who have family history of deafness. The patient does not have hearing impairment. ATP6V0A4 gene sequencing demonstrated that there were 2 heterozygous mutations, c.1376C>T and c.1029+5G>A, in gene ATP6V0A4. c.1376C > T (p.Ser459Phe) is a kind of missense mutation in gene ATP6V0A4. c.1029+5G>A is a kind of intragenic mutation near the cutting area of gene ATP6V0A4. ATP6V0A4 gene mutation study substantiated the autosomal recessive dRTA without hearing impairment in the patient. This case report emphasizes the significance of early diagnosis and genetic screening of recessive forms of dRTA independent of hearing status and offer suitable intervention to treat dRTA as well as diminish the influence of SNHL on the child’s learning and communication in daily life.

Keywords
Renal tubular acidosis; Homeostasis; Electrolytes; Hearing impairment; ATP6V0A4 gene; Mutation