A gene that helps explain why some individuals are more likely to develop allergies is reported online in this week's Nature Immunology. These findings increase our understanding of how immune cells that impact infectious, autoimmune, and allergic disease susceptibility are regulated.

'Type 2' immunity is necessary for resistance to parasites but can also lead to allergic reactions. A team led by Mark Bix and Masato Kubo trace the genetic bias underlying development of 'type 2' immunity to expression of the gene Mina.

Mina encodes a protein that blocks early expression of interleukin 4 (IL-4), a key molecule responsible for inducing allergic-like immune responses. Immune cells from allergic-prone mice express less Mina protein and consequently express IL-4 more readily than those from strains lacking this bias.