SNP Shot: Genomic Insights

Renal tubular acidosis with deafness is a condition involving both kidney issues and hearing loss. The kidneys' normal function is to filter waste and fluids, excreting them as urine. However, in individuals with this disorder, the kidneys fail to adequately remove acids, leading to their reabsorption into the bloodstream and causing the blood to become overly acidic. This condition, known as metabolic acidosis, results in varying degrees of symptoms, including nausea, vomiting, and dehydration. Infants with the condition often experience feeding difficulties and struggle to gain weight (failure to thrive). Short stature is common in children and adults, and many develop kidney stones.

The metabolic acidosis associated with renal tubular acidosis with deafness can also weaken bones, resulting in rickets in children and osteomalacia in adults. This bone disorder manifests as bone pain, bowed legs, and difficulty walking. In rare instances, individuals may experience hypokalemic paralysis, characterized by severe muscle weakness due to low potassium levels in the blood (hypokalemia).

The hearing loss experienced by individuals with renal tubular acidosis with deafness is typically sensorineural, caused by inner ear changes. It generally begins between childhood and young adulthood and progressively worsens. Many affected individuals exhibit an inner ear abnormality called enlarged vestibular aqueduct, visible through medical imaging. The vestibular aqueduct is a bony canal connecting the inner ear to the temporal bone of the skull, extending toward the brain. The exact link between an enlarged vestibular aqueduct and hearing loss remains unclear. However, in this disorder, it is often associated with hearing loss that begins during childhood.

Inheritance:

This condition follows an autosomal recessive inheritance pattern. This means that an individual must inherit a mutated copy of the responsible gene from each parent to develop the condition. The parents, while carrying one copy of the mutated gene each, usually do not exhibit any signs or symptoms of the disorder themselves.