The appearance of the rats here at R0d3nts is controlled by their genetics! Although the genetics of the rats here function very similarly to the genetics of their real world counterparts, they're significantly less convoluted and much more condensed.
The rats' genetics are controlled by 13 genes, each made up of two alleles, located at specific loci (singular "locus") along the chromosome. In this guide we have an explanation of how every allele combination at each locus will effect the physical appearance of your rats!
<aside> 🧬 AA BB DD RR EE LL GG SS TT CC HH VV MM
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When an asterixis () is used in describing a allele combination, such a "A*", it means that the second allele is irrelevant / could be anything. Both AA and Aa would result in an agouti rat, so, when the guide is discussing how agouti interacts with other genes it may use A* in the notation.*