We summarise the well-known examples, such as α-globin deletion and susceptibility to severe malaria, as well as more recent controversies, such as the extensive CNV of the chemokine gene CCL3L1 and HIV infection.
The role of copy number variation of the CCL3L1 gene, encoding MIP1α, in contributing to the host variation in susceptibility and response to HIV infection is controversial.
A high CCL3L1 copy number (>2) was associated with an 80% reduced risk of acquiring HIV infection after adjusting for age, sex, HCV and HBV status, CCR5-Delta32 polymorphism, and IDU duration (odds ratio, 0.20; 95% confidence interval, 0.09-0.45).
CCL3L1-CCR5 genotypes may impact on the dynamics of the HIV epidemic and, consequently, the observed heterogeneous global distribution of HIV infection.
CCL3L1-CCR5 genotypes may impact on the dynamics of the HIV epidemic and, consequently, the observed heterogeneous global distribution of HIV infection.
This study confirms a crucial protective role of CCL3L1 from both HIV infection and disease progression, highlighting a previously not described functional up-regulation of this chemokine variant in both HIV-positive and -negative persons infected with HTLV-2.