Exonic structure of AHI1 and the Jouberin protein, including patient mutations. A, The gene encoded in ∼215 kb of genomic DNA and that contains 31 exons, 2 of which are alternatively spliced, producing shorter isoforms. Patient mutations are indicated by arrows and occur in exon 8 and exon 10. B, The predicted full-length human Jouberin protein gives a 1,196-aa message with seven WD40 repeats and an SH3 domain.