Experimental aspects of copy number variant assays at CCL3L1

Copy number variants (CNVs) are duplicated or deleted segments of the genome that vary in size from a few bases to several kb and comprise a significant proportion of normal genomic variation1. The role of population-wide CNVs in disease has only recently come under investigation2,3. The chemokine (C-C) motif receptor 5, CCR5, on chromosome 3p21 has been associated with resistance to HIV-1 infection2. One of its ligands, CCL3L1, is encoded by a gene that lies in a CNV on chromosome 17q12,4 which includes another CCR5 ligand, CCL4L1, (Supplementary Figure 1) both of which have been reported to be associated with HIV-1/AIDS susceptibility2,5,6. CCR5 is associated with type 1 diabetes (T1D)7, and hence we hypothesised that CCL3L1 was also associated with T1D.