Human CD28 and CTLA-4 Ig superfamily genes are located on chromosome 2 at bands q33-q34.
CD28 is a cell surface molecule present on most peripheral T cells which has been implied in the amplification of the T-cell response in vitro. Using in situ hybridization on human prometaphase cells, we have found that the human CD28 gene maps to chromosome 2 at bands q33-q34, as shown previously for the CTLA-4 gene. CD28 and CTLA-4 are both members of the Ig superfamily, where they define a subgroup of membrane-bound single V domains. Their chromosomal proximity and their close structural relationship suggest that these two genes could be the result of the duplication of a common evolutionary precursor and may share some functional properties.
Lafage-Pochitaloff
M
M
INSERM U. 119, Institut Paoli-Calmettes, Marseille, France.
Costello
R
R
Couez
D
D
Simonetti
J
J
Mannoni
P
P
Mawas
C
C
Olive
D
D
D015703:Antigens, CD / Q000235:genetics*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics*; D001345:Autoradiography; D018106:CD28 Antigens; D002874:Chromosome Mapping; D002889:Chromosomes, Human, Pair 2 / Q000032:analysis*; D006801:Humans; D008297:Male; D005810:Multigene Family; D009693:Nucleic Acid Hybridization
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018106:CD28 Antigens