IMGT Repertoire (IG and TR)

Allotypes: Human (Homo sapiens) IGHC

Here you are: IMGT Web resources > IMGT Repertoire (IG and TR) > 2. Proteins and alleles

Citing this page: Lefranc, M.-P. and Lefranc, G. Human Gm, Km and Am allotypes and their molecular characterization: a remarkable demonstration of polymorphism In: B. Tait, F. Christiansen (Eds.), Immunogenetics, chap. 34, Humana Press, Springer, New York, USA. Methods Mol. Biol. 2012; 882, 635-680. PMID: 22665258 LIGM: 406

G3m allotypes

IMGT G3m allele butterfly
G3m allotypes on Homo sapiens gamma3 chains

IMGT G3m allele butterfly

Fig. 1. 'IMGT G3m allele butterfly' representation. The six most prevalent G3m alleles [1] are shown:

The first G3m mosaic on the CH3 domain of IGHG3 is illustrated by the top part of each butterfly representation and corresponds to G3m11/nG3m11, G3m27 and the antithetical G3m10/G3m24, and G3m13/G3m6 allotypes. The second G3m mosaic on the CH3 domain of IGHG3 is illustrated by the bottom part of each butterfly representation and corresponds to the G3m26, and the antithetical G3m5/nG3m5/G3m28 allotypes.
Amino acids involved in the allotype expression and their position according to the IMGT unique numbering for C domain are indicated. Two allotypes are on the CH2 domain, G3m16 (Trp W83) and G3m21 (Leu L82). Before each G3m allele butterfly, G3m alleles are indicated with the simplified form (e.g., G3m5*) (1st line), the full nomenclature (2nd line) and the IGHG3 alleles are indicated on the 3rd line. Haplotypes to which the G3m alleles belong are indicated between square brackets. The IGHG3*08 (not shown) is unusual (G3m5, 14, 26 allele, with a silent G3m (10,11,13) owing to an Asn 44).

Reference to be quoted for the figure:

Lefranc, M.-P. and Lefranc, G., Methods Mol. Biol. 2012; 882, 635-680. PMID: 22665258 LIGM: 406 [1]

G3m allotypes on Homo sapiens gamma3 chains

Fig. 2. G3m allotypes localizations on Homo sapiens IG gamma3 chains [1].

G3m16 (tryptophan Trp W83) and G3m21 (leucine Leu L82), nG3m21 (proline Pro P82) are located on the CH2. The other G3m allotypes form two mosaics on the CH3. G3m 26 (R115), G3m5 (R115, F116), G3m28 (R115, Y116), nG3m5 (H115, Y116), G3m14 (M84, R115, F116) and G3m15 (M39, H115, Y116) form a first mosaic. G3m11 (S44), nG3m11 (N44), G3m10 (S44, I101), G3m24 (S44, V101), G3m27 (I101), G3m6 (S44, E98), G3m13 (S44, Q98) form a second mosaic [1].

In the CH3, the combination of M84 with G3m5 (R115, F116) characterizes the G3m14 allotype of the G3m5* and G3m6* alleles. In contrast, the combination of M84 with G3m28 (R115, Y116) does not define a novel allotype (for that reason, M84 although present is not displayed in the butterfly representation of the G3m21* allele (G3m21, 26, 27, 28) which corresponds to the IGHG3*14, *15, *16 alleles [1].