Rearranged immunoglobulin variable region heavy chain and light chain sequence analysis of 43 single sorted cells from CLL subject 012. Sequence alignment for 14 subgroups (A-N) of the VH4-59 (A) and Vk1-L12 (B) immunoglobulin genes sequenced from 43 single CLL cells from subject 012. Dashes signify identical bases, and dots represent the absence of bases compared with the germ line genes for VH4-59 and Vk1-L12. Replacement mutations are shown in uppercase, and silent mutations are shown in lowercase. The number of sequences or CLL cells in each group is indicated and is preceded by an x.