December 1, 2001

12:01 PM

CCR5This gene encodes for a protein on T cells that allows HIV to enter and replicate. It's also another reason why AIDS has less of an effect on European populations - 10-15% of Northern Europeans carry a defect that doesn't allow the attachment, so 1% or so is homozygous for the 'faulty' gene and appears to be completely resistant to HIV/AIDS.
posted by phoenix enflamed (1 comment total)

The theory is that it was selected by bubonic plague - due to the large similar DNA sequence surrounding the mutation, it can be dated to the appropriate era. It may have interacted directly with the plague's mechanism of attack, or perhaps was more similar to how malaria selected for sickle cell anemia in Africa and cholera selected for cystic fibrosis in Europe.
posted by phoenix enflamed at 12:02 PM on December 1, 2001