Developmental expression pattern in cerebellum and tissue distribution of CAPS2 splice variants. (A) Exon 3-skipping in normal mice. RT-PCR analysis of CAPS2 mRNA in total RNA from developing mouse cerebella (P0, P3, P7, P12, P21, and P56) and various tissues (P7 and P21). An aberrant alternatively spliced CAPS2 mRNA that lacks exon 3 was previously observed in some autistic patients . A single major band (502 bp) is apparent in all samples in which CAPS2 is expressed. A smaller band (169 bp) that would indicate skipping of exon 3 was not detected. The primers used are indicated on the corresponding exons by arrows. Lane M, 100-bp ladder molecular size marker (from 100 bp at the bottom to 1500 bp at the top). (B) The expression profile of CAPS2 isoforms in developing mouse cerebella at E18, P0, P3, P7, P12, P15, P21, and P56 was analyzed by RT-PCR. (C) The tissue distribution of CAPS2 isoform expression in P21 mice was analyzed by RT-PCR. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as a control. The numbers of PCR cycles are shown in parenthesis.