Background:Polymorphism of HIV co-receptor,CC chemokine receptor 5 (CCRS),varies with geographical location and may potentially affect HIV-1 infection and disease progression.Method:Two groups of Chinese adults residing in Hong Kong were recruited:(1) 785 HIV healthy donors and (2) 314 HIV+ patients.CCR5 mutations were identified from the study subjects by sequencing.Five either most prevalent or possible clinically significant mutant genes were cloned and their effects on HIV infection were analyzed by a series of in vitro experiments,including detections of their transcription levels,expression levels,conformational changes,and HIV co-receptor function.