Researchers at the Institute of Child Health in London have found that two in thousand children is carrying a gene variation that turns them prone to hearing loss when using a common hospital antibiotic like aminoglycosides. Even normal doses of this antibiotic, widely used on children, can permanently harm hearing. Researchers recommend to genetically screen out groups of patients who will almost certainly receive aminoglycoside antibiotics, to see if they carry the mutation, before administering the antibiotics.