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Correspondence between V numberings

IMGT unique numbering (Lefranc) and structural correspondence for the different CDR-IMGT lengths with the diverse Kabat/Chothia numberings and CDR/loop delimitations (horizontal display per locus): IGHV and VH

Correspondence is shown for CDR1-IMGT and CDR2-IMGT lengths found in human and mouse germline V genes.
Correspondence for CDR3-IMGT is shown for examples quoted in Lefranc et al. 2003 [1].

CDR1-IMGT

CDR1-IMGT
length		 anchor
position		 CDR1-IMGT anchor
position
C W
IMGT 12 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
[2] (1) 22 23 24 25 26 27 28 29 30 31 32 33 34 35 35A 35B 35C 35D 36
IMGT 11 23 24 25 26 27 28 29 30 31 32 - 34 35 36 37 38 39 40 41
[2] (1) 22 23 24 25 26 27 28 29 30 31 - 32 33 34 35 35A 35B 35C 36
IMGT 10 23 24 25 26 27 28 29 30 31 - - 34 35 36 37 38 39 40 41
[2] 22 23 24 25 26 27 28 29 30 - - 31 32 33 34 35 35A 35B 36
[5] 22 23 24 25 26 27 28 29 30 - - 31 31a 31b 32 33 34 35 36
IMGT 9 23 24 25 26 27 28 29 30 31 - - - 35 36 37 38 39 40 41
[2] 22 23 24 25 26 27 28 29 30 - - - 31 32 33 34 35 35A 36
[5] 22 23 24 25 26 27 28 29 30 - - - 31 31a 32 33 34 35 36
IMGT 8 23 24 25 26 27 28 29 30 - - - - 35 36 37 38 39 40 41
[2] 22 23 24 25 26 27 28 29 - - - - 30 31 32 33 34 35 36
[3-5] 22 23 24 25 26 27 28 29 - - - - 30 31 32 33 34 35 36

CDR2-IMGT

CDR2-IMGT
length		 anchor
position		 CDR2-IMGT anchor
position
IMGT 10 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 - 74
[2] 50 51 52 52A 52B 52C 53 54 55 56 57 58 59 60 61 62 63 64 - 65
[3-5] 50 51 52 52a 52b 52c 53 54 55 56 57 58 59 60 61 62 63 64 - 65
IMGT 9 55 56 57 58 59 60 - 62 63 64 65 66 67 68 69 70 71 72 - 74
[2] 50 51 52 52A 52B 53 - 54 55 56 57 58 59 60 61 62 63 64 - 65
[3-5] 50 51 52 52a 52b 53 - 54 55 56 57 58 59 60 61 62 63 64 - 65
IMGT 8 55 56 57 58 59 - - 62 63 64 65 66 67 68 69 70 71 72 - 74
[2] 50 51 52 52A 53 - - 54 55 56 57 58 59 60 61 62 63 64 - 65
[3-5] 50 51 52 52a 53 - - 54 55 56 57 58 59 60 61 62 63 64 - 65
IMGT 7 55 56 57 58 59 - - - 63 64 65 66 67 68 69 70 71 72 - 74
[2] 50 51 52 53 54 - - - 55 56 57 58 59 60 61 62 63 64 - 65
[3-5] 50 51 52 53 54 - - - 55 56 57 58 59 60 61 62 63 64 - 65
IMGT 6 55 56 57 58 - - - - 63 64 65 66 67 68 69 70 71 72 - 74
[2] 50 51 52 53 - - - - 55 56 57 58 59 60 61 62 63 64 - 65
[3-5] 50 51 52 53 - - - - 55 56 57 58 59 60 61 62 63 64 - 65

CDR3-IMGT

CDR3-IMGT
length		 anchor
position		 CDR3-IMGT anchor
position
C W
IMGT 21 104 105 106 107 108 109 110 111 111.1 111.2 111.3 111.4 112.4 112.3 112.2 112.1 112 113 114 115 116 117 118
[2] 92 93 94 95 96 97 98 99 100 100A 100B 100C 100D 100E 100F 100G 100H 100I 100J 100K 101 102 103
[3] 92 93 94 95 96 97 98 99 100 100a 100b 100c 100d 100e 100f 100g 100h 100i 100j 100k 101 102 103
IMGT 20 104 105 106 107 108 109 110 111 111.1 111.2 111.3 - 112.4 112.3 112.2 112.1 112 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 98 99 100 100A 100B - 100C 100D 100E 100F 100G 100H 100I 100J 101 102 103
IMGT 19 104 105 106 107 108 109 110 111 111.1 111.2 111.3 - - 112.3 112.2 112.1 112 113 114 115 116 117 118
[2] 92 93 94 95 96 97 98 99 100 100A 100B - - 100C 100D 100E 100F 100G 100H 100I 101 102 103
[3] 92 93 94 95 96 97 98 99 100 100a 100b - - 100c 100d 100e 100f 100g 100h 100i 101 102 103
IMGT 18 104 105 106 107 108 109 110 111 111.1 111.2 - - - 112.3 112.2 112.1 112 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 98 99 100 100A - - - 100B 100C 100D 100E 100F 100G 100H 101 102 103
IMGT 17 104 105 106 107 108 109 110 111 111.1 111.2 - - - - 112.2 112.1 112 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 98 99 100 100A - - - - 100B 100C 100D 100E 100F 100G 101 102 103
IMGT 16 104 105 106 107 108 109 110 111 111.1 - - - - - 112.2 112.1 112 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 98 99 100 - - - - - 100A 100B 100C 100D 100E 100F 101 102 103
IMGT 15 104 105 106 107 108 109 110 111 111.1 - - - - - - 112.1 112 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 98 99 100 - - - - - - 100A 100B 100C 100D 100E 101 102 103
IMGT 14 104 105 106 107 108 109 110 111 - - - - - - - 112.1 112 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 98 99 - - - - - - - 100 100A 100B 100C 100D 101 102 103
IMGT 13 104 105 106 107 108 109 110 111 - - - - - - - - 112 113 114 115 116 117 118
[2] 92 93 94 95 96 97 98 99 - - - - - - - - 100 100A 100B 100C 101 102 103
[3] 92 93 94 95 96 97 98 99 - - - - - - - - 100 100a 100b 100c 101 102 103
IMGT 12 104 105 106 107 108 109 110 - - - - - - - - - 112 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 98 - - - - - - - - - 99 100 100A 100B 101 102 103
IMGT 11 104 105 106 107 108 109 110 - - - - - - - - - - 113 114 115 116 117 118
[2] 92 93 94 95 96 97 98 - - - - - - - - - - 99 100 100A 101 102 103
[3] 92 93 94 95 96 97 98 - - - - - - - - - - 99 100 100a 101 102 103
IMGT 10 104 105 106 107 108 109 - - - - - - - - - - - 113 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 - - - - - - - - - - - 98 99 100 101 102 103
IMGT 9 104 105 106 107 108 109 - - - - - - - - - - - - 114 115 116 117 118
[2] (1) 92 93 94 95 96 97 - - - - - - - - - - - - 99 100 101 102 103

Light-grey background correspond to previous CDR delimitation in [2-5].
Colors are according to IMGT color menu for CDR-IMGT and IMGT color menu for sequence alignments.

IMGT note:
(1) Added for completeness although there is no example in [2].

IMGT references:
[1] Lefranc, M.-P. et al. "IMGT unique numbering for immunoglobulin and T cell receptor variable domains and Ig superfamily V-like domains"
Dev. Comp. Immunol., 27, 55-77 (2003). PMID: 12477501 pdf with permission from Elsevier
[2] Kabat, E.A. et al., In: Sequences of Proteins of Immunological Interest, NIH Publication, 91-3242 (1991).
[3] Chothia, C. and Lesk, A.M., J. Mol. Biol., 196, 901-917 (1987).
[4] Chothia, C. et al., Nature, 342, 877-883 (1989).
[5] Al-Lazikani, B. et al., J. Mol. Biol., 273, 927-948 (1997).