Fig. 3.

Exon 2 motif type and subtype variation generates diversified allelic lineages. A Comparison of two subtypes of -SAG-type 2b alleles (-SAG-motif in bold; defined in mixed animal surveys are distinguished by grey shading). Polymorphisms representing point mutations (reverse image) account for additional variation. B Alleles from additional animals exhibit subtype variation (reverse image) from (A). C Shared polymorphisms in EX2 (boxed) extend to adjacent introns (e.g., SW01 and LP07) or intron variation in otherwise conserved alleles (e.g., LP02 and PACV). Sequence differences can be extensive (e.g., LP10). D Schematic illustration of EX2 polymorphism and relatedness; EX2 types and subtype variants give rise to diverse allelic lineages. In this example, three types of VCBP2 alleles [defined by core EX2 peptide motifs (i.e., “types”): DREY, SAG and SASY] can be classified into subtypes, exhibiting further polymorphic variation (terminal branches; subtype variants) that can result in additional subtype lineages (e.g., NAG and SAAAG). Some VCBP2 alleles (i.e., alternative EX2 types) represent paralogous genes from haplotype-specific CNVs. Bold lines for -NAG- and -SAAG- imply novel lineages of allele types. PacV=Bf Pac 47J9. Numbers in (A) refer to individual sequence clones. Figure in (C) is not meant to depict phylogenetic relationships