Mutated pseudogene G8 sequences. The G8 cDNA sequence, consisting of leader, leader intron, germline VH gene segment directly spliced to C region, is aligned to the most closely related functional gene, G1 (top). The genomic germline G1 sequence shows leader, leader intron with splice sites (indicated in lower case) and the VH gene segment demarcated into framework (FR) and complementarity-determining region (CDR, underlined). The recombination signal sequences (heptamer, spacer, nonamer) are labeled. G8 is nonfunctional, due to a mutation disabling the leader intron splice acceptor site. G8 mutants 15, 28 and 31 are compared with the G8 cDNA, with dots representing identity and dashes gaps. The PCR primer is shown in italics.