This allele contains an insertion of DNA comprised of a 5.5kb virus-like element, VL30, into the first intron of the agouti gene. The VL30 element does not contain the additional 5.5 kb sequence, flanked by 526 bp of direct repeats (beta4 retroviral sequence), found in a. This allele is present in MOLF/EiJ and MSM/Ms strains.