A 3-year-old Mississippi child born with HIV and treated with a combination of antiviral drugs unusually early continues to do well and remains free of active infection 18 months after all treatment ceased, according to an updated case report published Oct. 23 in the New England Journal of Medicine.

Errors in the human genetic code that arise from mismatched nucleotide base pairs in the DNA double helix can lead to cancer and other disorders. In microbes, such errors provide the basis for adaption to environmental stress. As one of the first responders to these genetic errors, a small protein called MutS – for "Mutator S" – controls the integrity of genomes across a wide range of organisms, from microbes to humans. Understanding the repair process holds importance for an equally impressive range of applications, including synthetic biology, microbial adaption and pathogenesis.