KRT1 and infection: These polyclonal infections mostly involved trimorphic and dimorphic allelic family combinations: 27.4% (23/84) of K1/MAD20/RO33, 16.7% (14/84) of MAD20/RO33, 14.3% (12/84) of K1/RO33 and 5.9% (5/84) of K1/MAD20.