- Isoform 1 is the canonical sequence with 211 amino acids and it weighs 22418 Da.

MANSGLQLLGFSMALLGWVGLVACTAIPQWQMSSYAGDNIITAQAMYKGLWMDCVTQSTGMMSCKMYDSVLALSA
ALQATRALMVVSLVLGFLAMFVATMGMKCTRCGGDDKVKKARIAMGGGIIFIVAGLAALVACSWYGHQIVTDFYNPLI
PTNIKYEFGPAIFIGWAGSALVILGGALLSCSCPGNESKAGYRVPRSYPKSNSSKEYV

- Isoform 2 contains 145 amino acids, with a shorter C-terminus, lacking amino acids 159 to 211 in comparison to isoform 1. It weighs 15156 Da.

MANSGLQLLGFSMALLGWVGLVACTAIPQWQMSSYAGDNIITAQAMYKGLWMDCVTQSTGMMSCKMYDSVLALSA
ALQATRALMVVSLVLGFLAMFVATMGMKCTRCGGDDKVKKARIAMGGGIIFIVAGMSLALPSLLAGQGLP

CLDN-7 is an integral membrane protein with four hydrophobic transmembrane domains and two extracellular loops which appear to be implicated in tight junction formation and with their amino- and carboxy-terminal tails extending into the cytoplasm (figure 2).

Polymorphisms
According to the Ensembl database 12 variations could be present in the transcripts (variants 1/2) of CLDN-7:
Position 963/396 of mRNA a synonymous G/A polymorphism at position 61 of the amino acid sequence.
Position 979/412 of mRNA a non-synonymous G/T polymorphism at position 77 of the amino acid sequence. Switching an Ala for an Asp residue. SIFT deleterious.
Position 1299/732 of mRNA a non-synonymous C/T polymorphism at position 397 of the amino acid sequence. Switching an Ala for an Thr residue. SIFT tolerated.
Position 1425/858 of mRNA a non-synonymous C/A polymorphism at position 523 of the amino acid sequence. Switching an Val for an Phe residue. SIFT deleterious.
Position 1492/925 of mRNA a non-synonymous A/G polymorphism at position 590 of the amino acid sequence. Switching an Val for an Ala residue. SIFT tolerated.
Position 1508/941 of mRNA a synonymous A/C polymorphism at position 606 of the amino acid sequence.