ABSTRACT
<p><b>OBJECTIVE</b>To study the genetic diversity of HIV-1 nef genes from a patient with AIDS dementia complex(ADC) , so as to research the amino acid variability and the pathogenesis of ADC.</p><p><b>METHODS</b>The nef gene was amplified with PCR from genomic DNA which was extracted from spleen and different brain tissues(basal ganglia, frontal gray matter, meninges, temporal lobe)of a patient who died of ADC. PCR products were cloned into the pMD19-T vector, after transformation and selection by ampicillin and blue/white spotting. Five of positive clones were sequenced and confirmed with BLAST. HIV-1 nef sequences were processed with BioEdit and MEGA4 to do Neighbor-Joining tree, p-Distances, and values of ds/dn.</p><p><b>RESULTS</b>The samples were all identified as HIV-1 B and genetic variation exists in HIV-1 nef gene isolated from different tissues compared with HXB2. In addition,part of the changes were different between periphery and brain.</p><p><b>CONCLUSION</b>Variations exist in the HIV-1 nef gene extracted from the ADC patient and the variations from peripheral and central nerve tissues were different,these variations may change the function of Nef,and it needs more research.</p>