Though homozygous 7/7R was the dominant genotype in our research subjects although many different DC-SIGN allelic combinations were found in our research. In order to illustrate the missing fragments of each repeat region, and to identify the genotype of repeat alleles within the neck region, we draw a sketch map of the DC-SIGN gene, as described previously.6,7 The map shows that the first, second, and eighth repeat alleles were conserved among all samples and were rarely absent (Figure).
Another important factor is that DC-SIGN translated from mRNA rather than from DNA may have great significance on HIV infection. Different DC-SIGN structure from different recombination of DC-SIGN mRNA may directly interact with HIV and could have a potential effect on HIV infection. In our present study, we determined variants of the DC-SIGN neck region from HIV-1 infected and uninfected individuals, respectively. We show that variations within DC-SIGN are significantly more common in the HIV infected cohort than in the control group. Differing from previous report that heterozygous DC-SIGN is not available in HIV-1(+) individuals,13 our date suggest heterozygous DC-SIGN in the Chinese Han population is detectable and heterozygous DC-SIGN does not have an impact on HIV infection.
It should be pointed that further research is urgently required to explore potential the significance for the presence of these mutations in the HIV-1 seropositive populations. For example, whether variations of DC-SIGN are related to HIV/AIDS progress or not will require a detailed study. Our results provide a starting point to understanding why mutation rates in DC-SIGN are increased in HIV infected individuals.
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