Examples of C_H duplication and deletion polymorphisms. The upper fiber shows haplotype B, which has an extra Cγ signal in the 3′ cluster as compared with haplotype A (Fig1), and was present at a frequency of 37.5% in our series. The second fiber has two extra Cγ signals in the 3′ cluster. The third fiber shows an example of the second most frequent type of polymorphism, appearing as a multigene duplication. The lower two fibers are the two germline alleles of one HCL patient, allele 1 having a multigene deletion, allele 2 having a more complex pattern, probably the result of multiple deletion/duplication events. On the alleles in this figure most Cγ and C genes could not be identified and are indicated only with γ and .