Figure 7.

Phylogenetic tree of 40 functional V_H genes (loci) and 6 additional polymorphic alleles from humans. This tree was constructed by using Jukes–Cantor distances for the nucleotide sequences (228 bp) of framework regions 1, 2, and 3 (14). Loci 1–2, 3–30, and 4–31 are represented by three alleles. Gene and allelic notations are the same as those of Honjo and Matsuda (53) and the V BASE database (54), from which the sequence data were obtained. The human V_H genes are classified into seven families, and the first number of each gene symbol designates the family number, whereas the second number refers to the order of the chromosomal location from the D_H gene region.