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New TAP2 polymorphisms in Africans.

J Tang·S Allen·E Karita·R Musonda·R A Kaslow
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Abstract

Polymorphisms in genes encoding transporters associated with antigen processing (TAP) have been associated with heterogeneity of disease progression in HIV-1-infected homosexual men. In our recent AIDS-related studies of cohorts from Rwanda and Zambia, four new polymorphic sites in the TAP2 coding region were detected by single-strand conformation polymorphism (SSCP) and confirmed by bi-directional nucleotide sequencing and restriction enzyme digestion. The first, a substitution of Thr (GCC) for Ala (ACC) at codon position 374 in exon 5, was found in about 13% of Rwandans and Zambians (n=213). The remaining 3 new polymorphisms were seen in the 7th exon with changes of 458Thr-ACG to ACA, 466Gly-GGG to GGA, and 467Val-GTT to Ile-ATT, respectively These 3 variants occurred exclusively on the same chromosome and appeared to have arisen together from the 374Thr-bearing allele. Analyses of the relationship between the 374Thr-467Ile segment and the nearby markers in DQB1 and DRB1 suggested the existence of a unique extended haplotype related to these newly identified variants.

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ATP Binding Cassette Transporter, Subfamily B, Member 3ATP-Binding Cassette TransportersBlack PeopleGenetic MarkersGenotypeHumansMajor Histocompatibility ComplexPolymorphism, GeneticRwandaZambiaJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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J Tang, S Allen, E Karita, R Musonda, R A Kaslow. 1998. New TAP2 polymorphisms in Africans.. https://doi.org/10.1111/j.1399-0039.1998.tb02992.x

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