A new assay for CCR5del32 mutation: genotyping through the number of fragments amplified.

: CCR5 is a coreceptor for the entry of HIV into CD4+ cells and some of its natural mutants possess potential protection against HIV-1 infection. Individuals with the CCR5-delta32 genotype have a lower possibility of being infected with HIV and take longer to progress to AIDS if infected. The present study demonstrated a new primer extension assay for genetic analysis of the CCR5del32 mutation: each genotype is determined by a specific number of fragments amplified. Quick and efficient screening and testing of this specific genotype is clinically useful in epidemiological study, risk analysis, and determining donors for allogenic stem cell transplantation.