Alternative splicing of the Anopheles gambiae Down syndrome cell adhesion molecule (DSCAM). This Ig domain protein has multiple alternative splice exons within its IG regions. The above image shows the different domains found within the protein and the exons encoding these domains. Exons 4, 6, 10 and 14 are alternately spliced with 14, 16, 38 and 2 alternate exons respectively. The different combinations of these exons can give rise to 31 920 splice forms. The protein plays a pathogen recognition role, with the large number of isoforms allowing it to recognize, bind and respond to a wide array of different pathogens.