Rare genetic variant contributes to common cold susceptibility

A rare genetic mutation can increase susceptibility to the common cold, according to a US National Institute of Allergy and Infectious Diseases-led team of researchers. The NIAID-led team homed in on this variant by sequencing the whole exome of a young girl who began experiencing life-threatening respiratory infections shortly after birth. As the team reported today in the Journal of Experimental Medicine, the girl has a homozygous missense mutation in the IFIH1 gene that led her to make dysfunctional MDA5 proteins and prevented her immune system from mounting a response against human rhinoviruses. “The human immune response to common cold viruses is poorly understood,” NIAID Director Anthony Fauci said in a statement. “By investigating this unique case, our researchers not only helped this child, but also helped answer some important scientific questions about these ubiquitous infections that affect nearly everyone.” There are some 18 billion upper respiratory infections worldwide each year, many of...