CLDN6 and Hyperkeratosis: The skin of 2-week-old mice overexpressing a shorter deletion in the cytoplasmic tail domain of Cldn6 (Inv-Cldn6-CΔ196) have striking histological abnormalities compared with the wild-type, as evidenced by epidermal hyperplasia and hyperkeratosis, which is similar to the skin of Inv-Cldn6 and Inv-Cldn6-CΔ187 mice [45].