[A10005] Distribution of the CCR5 gene 32 base pair deletion and CCR5 expression in Chinese minorities

14th International AIDS Conference

Barcelona, Spain — July 7-12, 2002

[TITLE:] Distribution of the CCR5 gene 32 base pair deletion and CCR5 expression in Chinese minorities

[AUTHOR(S):] T. Feng, A.P. Ni¹, H. Irving, M.S. Cohen²

Int Conf AIDS. 2002 Jul 7-12;14:Abstract No. A10005

BACKGROUND: A mutant allele of the β-chemokine receptor gene CCR5 bearing a 32-basepair (bp) deletion (denoted by Dccr5) which prevents cell invasion by the primary transmitting strains of HIV-1 has recently been characterized. Homozygotes for the mutation are resistant to infection, even after repeated high-risk exposures. The consequence of the heterozygous state is not clear, but it may delay the progression to AIDS in infected individuals. Epidemiologic evidence suggests that many of the 56 minority populations in China are at particularly high risk of acquiring HIV. To further characterize this risk we examined the HIV genetic diversity in a sub-set of these minorities.

METHODS: After obtaining written informed consent, demographic information and a blood sample were obtained from adults belonging to the Han, Meng, Zang, Weiwuer, Yi, Zhuang and Dai minorities. To get genotype and allele frequencies of CCR-5 and Dccr-5, we performed PCR on genomic DNA samples. Surface expression of CCR-5 was measured by flow cytometry. One-way ANOVA was used to determine mean statistical differences.

RESULTS: Samples from 10 members of each minority were examined. There was a heterozygote in Weiwuer minority and no mutations were found among the other 69 samples investigated.

	Han	Meng	Zang	Weiwuer	Yi	Zhuang	Dai*
CD3+CCR5+	28.5	25.4	24.3	25.4	26.4	23.5	37.2
CD4+CCR5+	9.9	9.6	9.2	8.2	9.5	10.0	15.6

The mean CCR5 expression of the Dai minority is significantly different from those of all other minorities both for CD3+CCR5+ and CD4+CCR5+ (* P value <0.001, one way ANOVA).

DISCUSSIONS: This pilot study shows the Dai minority may have a greater CCR-5 dependent susceptibility to HIV acquisition compared to the other minorities investigated. Because of this added risk factor, special prevention resources should be focused on this minority. Further studies of the biological risk in the Dai community is warranted.

Presenting author: Tao Feng

1Peking Union Medical College Hospital, Shuaifuyuan 1#, Dongchengqu, Peking Union Medical College Hospital, Beijing, China.

2University of North Carolina, Chapel Hill, United States.

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