The present invention relates to consensus nucleotide and protein sequences for HIV- 1 Clade A antigens, and to nucleotide and protein sequences for Clade A antigens from circulating HIV-I field isolates wherein the antigen sequences are closely related to the these consensus sequences. In a preferred embodiment, the present invention relates to HIV-I Clade A transgenes that are derived from such sequences, and that encode either HIV-I Clade A Gag, Pol (RT and Int), and Nef (referred to as GRIN), HIV-I Clade A Gag, RT, and Nef (referred to as (GRN), or HIV-I Clade A Env. The invention also relates to vectors containing such transgenes, including in preferred embodiment, adenovirus vectors containing such transgenes. The invention also relates to immunogenic compositions comprising the HIV-I Clade A antigens, nucleotide sequences, vectors, or transgenes of the invention, and to methods of generating an immune response against HIV in a subject by administering an effective amount of such immunogenic compositions.
