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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): IGLV and V-LAMBDA

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 9 23 24 25 26 27 28 29 30 31 - - - 35 36 37 38 39 40 41
[2] 23 24 25 26 27 27A 27B 27C 28 - - - 29 30 31 32 33 34 35
[3] 23 24 25 26 27 28 29 30 30a - - - 30b 30c 31 32 33 34 35
[5] 23 24 25 26 27 28 29 30 30a - - - 30b 30c 31 32 33 34 35
IMGT 8 23 24 25 26 27 28 29 30 - - - - 35 36 37 38 39 40 41
[2] 23 24 25 26 27 27A 27B 28 - - - - 29 30 31 32 33 34 35
[3] 23 24 25 26 27 28 29 30 - - - - 30a 30b 31 32 33 34 35
[5] 23 24 25 26 27 28 29 30 - - - - 30a 30b 31 32 33 34 35
IMGT 7 23 24 25 26 27 28 29 30 - - - - - 36 37 38 39 40 41
[2] 23 24 25 26 27 27A 28 29 - - - - - 30 31 32 33 34 35
[5] 23 24 25 26 27 30 30a 30b - - - - - 30c 31 32 33 34 35
IMGT 6 23 24 25 26 27 28 29 - - - - - - 36 37 38 39 40 41
[2] 23 24 25 26 27 28 29 - - - - - - 30 31 32 33 34 35

CDR2-IMGT

CDR2-IMGT
length		 anchor
position		 CDR2-IMGT anchor
position
IMGT 8 55 56 57 58 59 - - 62 63 64 65 66 67 68 69 70 71 72 - 74
IMGT 7 55 56 57 58 59 - - - 63 64 65 66 67 68 69 70 71 72 - 74
IMGT 3 55 56 57 - - - - - - - 65 66 67 68 69 70 71 72 - 74
[2] 49 50 51 - - - - - - - 52 53 54 55 56 57 58 59 - 60
[3-5] 49 50 51 - - - - - - - 52 53 54 55 56 57 58 59 - 60

CDR3-IMGT

CDR3-IMGT
length		 anchor
position		 CDR3-IMGT anchor
position
C F
IMGT 15 104 105 106 107 108 109 110 111 111.1 112.1 112 113 114 115 116 117 118
[2] 88 89 90 91 92 93 94 95 95A 95B 95C 95D 95E 95F 96 97 98
IMGT 14 104 105 106 107 108 109 110 111 - 112.1 112 113 114 115 116 117 118
[2] (1) 88 89 90 91 92 93 94 95 - 95A 95B 95C 95D 95E 96 97 98
IMGT 13 104 105 106 107 108 109 110 111 - - 112 113 114 115 116 117 118
[2] (1) 88 89 90 91 92 93 94 95 - - 95A 95B 95C 95D 96 97 98
IMGT 12 104 105 106 107 108 109 110 - - - 112 113 114 115 116 117 118
[2] (1) 88 89 90 91 92 93 94 - - - 95 95A 95B 95C 96 97 98
IMGT 11 104 105 106 107 108 109 110 - - - - 113 114 115 116 117 118
[2] 88 89 90 91 92 93 94 - - - - 95 95A 95B 96 97 98
[3] 88 89 90 91 92 93 93a - - - - 93b 94 95 96 97 98
[5] 88 89 90 91 92 93 94 - - - - 95 95a 95b 96 97 98
IMGT 10 104 105 106 107 108 109 - - - - - 113 114 115 116 117 118
[2] (1) 88 89 90 91 92 93 - - - - - 94 95 95A 96 97 98
IMGT 9 104 105 106 107 108 109 - - - - - - 114 115 116 117 118
[2] 88 89 90 91 92 93 - - - - - - 94 95 96 97 98
[3,5] 88 89 90 91 92 93 - - - - - - 94 95 96 97 98

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).