The Sweet Blindness of Cats
A Genetic Mutation Story
Normal Tas1r2 Gene
Exon 1
Exon 2
Exon 3
Exon 4
Exon 5
Exon 6
Cat Tas1r2 Gene
Exon 1
Exon 2
Exon 3
Exon 4
Exon 5
Exon 6
247 bp deletion

A 247 base pair deletion in exon 3 of the Tas1r2 gene causes a frame shift mutation, creating premature stop codons in exons 4 and 6.

This prevents the formation of functional sweet taste receptors, which is why cats cannot taste sweet things!

Cats evolved as obligate carnivores, making sweet taste detection non-essential for their survival.