Four of the five human IGHG genes (G1, GP, G2, and G4) display a hinge region consisting of a unique exon. In contrast, IGHG3 exhibits a different structure in which the hinge is constituted by four or, less frequently, three exons. We report here the nucleotide sequence of a new 2-exon hinge G3 gene found in a Mandenka individual from Eastern Senegal. A comparison of this sequence with that of 4-exon and 3-exon hinge G3 genes suggests that the 3-exon and 2-exon hinge forms arose independently by deletion events in a 4-exon hinge gene.
The IGHG3 gene shows a structural polymorphism characterized by different hinge lengths: Sequence of a new 2-exon hinge gene
Dard, P.; Huck, S.; Frippiat, J. P.; Lefranc, G.; Langaney, A.; Lefranc, M. P.; SanchezMazas, A.
1997-01 / vol 99 / pages 138-141
activation; binding; molecule; chain constant-region; complement; igg3; immunoglobulins; segmental flexibility