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Correspondence between C numberings

Correspondence between the IMGT unique numbering for C-DOMAIN, the IMGT exon numbering, the Eu and Kabat numberings: Human IGHG

The IMGT unique numbering for C-DOMAIN is used in the Protein displays.

Hinge amino acids are shown at the bottom of the page.
Amino acids resulting from the splicing are shown between parentheses.

Colors of amino acids are according to IMGT Color menu for sequence alignments.

Strands, turns and loops for C-DOMAIN (5) IMGT unique numbering for C-DOMAIN CH1 Strands, turns and loops for C-DOMAIN (5) IMGT unique numbering for C-DOMAIN CH2 Strands, turns and loops for C-DOMAIN (5) IMGT unique numbering for C-DOMAIN CH3
IGHG1 amino acid translation J00228 (1) IMGT exon numbering Eu numbering [1] (1) Kabat numbering [2] IGHG1 amino acid translation J00228 (1) IMGT exon numbering Eu numbering [1] (1) Kabat numbering [2] IGHG1 amino acid translation J00228 (1) IMGT exon numbering Eu numbering [1] (1) Kabat numbering [2]
1-98 (98 aa) 1-110 (110 aa) (2) 1-107 (107 aa) (3)
118-215 231-340 341-446
1.8 - - - - 1.8 - - - - 1.8 - - - -
1.7 - - - - 1.7 - - - - 1.7 - - - -
1.6 - - - - 1.6 (A) 1 231 244 1.6 - - - -
1.5 - - - - 1.5 P 2 232 245 1.5 - - - -
1.4 (A) 1 118 114 1.4 E 3 233 246 1.4 (G) 1 341 361
1.3 S 2 119 115 1.3 L 4 234 247 1.3 Q 2 342 363
1.2 T 3 120 116 1.2 L 5 235 248 1.2 P 3 343 364
1.1 K 4 121 117 1.1 G 6 236 249 1.1 R 4 344 365
A-STRAND 1 G 5 122 118 A-STRAND 1 G 7 237 250 A-STRAND 1 E 5 345 366
2 P 6 123 119 2 P 8 238 251 2 P 6 346 367
3 S 7 124 120 3 S 9 239 252 3 Q 7 347 368
4 V 8 125 121 4 V 10 240 253 4 V 8 348 369
5 F 9 126 122 5 F 11 241 254 5 Y 9 349 370
6 P 10 127 123 6 L 12 242 255 6 T 10 350 371
7 L 11 128 124 7 F 13 243 256 7 L 11 351 372
8 A 12 129 125 8 P 14 244 257 8 P 12 352 373
9 P 13 130 126 9 P 15 245 258 9 P 13 353 374
10 S 14 131 127 10 K 16 246 259 10 S 14 354 375
11 S 15 132 128 11 P 17 247 260 11 R 15 355 376
12 K 16 133 129 12 K 18 248 261 12 D 16 356 377
13 S 17 134 130 13 D 19 249 262 13 E 17 357 378
14 T 18 135 133 14 T 20 250 263 14 L 18 358 381
15 S 19 136 134 15 L 21 251 264 15 T 19 359 382
AB-TURN 15.1 - - - - AB-TURN 15.1 M 22 252 265 AB-TURN 15.1 - - - -
15.2 - - - - 15.2 I 23 253 266 15.2 - - - -
15.3 - - - - 15.3 - - - - 15.3 - - - -
B-STRAND 16 G 20 137 135 B-STRAND 16 S 24 254 267 B-STRAND 16 K 20 360 383
17 G 21 138 136 17 R 25 255 268 17 N 21 361 384
18 T 22 139 137 18 T 26 256 269 18 Q 22 362 385
19 A 23 140 138 19 P 27 257 270 19 V 23 363 386
20 A 24 141 139 20 E 28 258 271 20 S 24 364 387
21 L 25 142 140 21 V 29 259 272 21 L 25 365 388
22 G 26 143 141 22 T 30 260 273 22 T 26 366 389
23 C 27 144 142 23 C 31 261 274 23 C 27 367 390
24 L 28 145 143 24 V 32 262 275 24 L 28 368 391
25 V 29 146 144 25 V 33 263 276 25 V 29 369 392
26 K 30 147 145 26 V 34 264 277 26 K 30 370 393
BC-LOOP 27 D 31 148 146 BC-LOOP 27 D 35 265 278 BC-LOOP 27 G 31 371 394
28 Y 32 149 147 28 V 36 266 279 28 F 32 372 395
29 F 33 150 148 29 S 37 267 280 29 Y 33 373 396
30 P 34 151 149 30 H 38 268 281 30 P 34 374 397
31 - - - - 31 E 39 269 282 31 - - - -
34 - - - - 34 D 40 270 283 34 - - - -
35 E 35 152 150 35 P 41 271 284 35 S 35 375 398
36 P 36 153 151 36 E 42 272 285 36 D 36 376 399
37 V 37 154 152 37 V 43 273 286 37 I 37 377 400
38 T 38 155 153 38 K 44 274 287 38 A 38 378 401
C-STRAND 39 V 39 156 154 C-STRAND 39 F 45 275 288 C-STRAND 39 V 39 379 402
40 S 40 157 156 40 N 46 276 289 40 E 40 380 405
41 W 41 158 157 41 W 47 277 290 41 W 41 381 406
42 N 42 159 162 42 Y 48 278 291 42 E 42 382 407
43 S 43 160 163 43 V 49 279 292 43 S 43 383 408
44 G 44 161 164 44 D 50 280 295 44 N 44 384 410
45 A 45 162 165 45 G 51 281 296 45 G 45 385 411
CD-STRAND 45.1 L 46 163 166 CD-STRAND 45.1 V 52 282 299 CD-STRAND 45.1 Q 46 386 414
45.2 T 47 164 167 45.2 E 53 283 300 45.2 P 47 387 415
45.3 S 48 165 168 45.3 V 54 284 301 45.3 E 48 388 416
45.4 - - - - 45.4 H 55 285 302 45.4 N 49 389 417
45.5 - - - - 45.5 - - - - 45.5 - - - -
45.6 - - - - 45.6 - - - - 45.6 - - - -
45.7 - - - - 45.7 - - - - 45.7 - - - -
D-STRAND 77 G 49 166 169 D-STRAND 77 N 56 286 303 D-STRAND 77 N 50 390 418
78 V 50 167 171 78 A 57 287 304 78 Y 51 391 419
79 H 51 168 172 79 K 58 288 305 79 K 52 392 420
80 T 52 169 173 80 T 59 289 306 80 T 53 393 421
81 F 53 170 174 81 K 60 290 307 81 T 54 394 422
82 P 54 171 175 82 P 61 291 308 82 P 55 395 423
83 A 55 172 176 83 R 62 292 309 83 P 56 396 424
84 V 56 173 177 84 E 63 293 310 84 V 57 397 425
DE-TURN 84.1 L 57 174 178 DE-TURN 84.1 E 64 294 311 DE-TURN 84.1 L 58 398 426
84.2 Q 58 175 179 84.2 Q 65 295 312 84.2 D 59 399 427
84.3 S 59 176 180 84.3 Y 66 296 313 84.3 S 60 400 428
84.4 S 60 177 182 84.4 N 67 297 314 84.4 D 61 401 430
84.5 - - - - 84.5 - - - - 84.5 - - - -
84.6 - - - - 84.6 - - - - 84.6 - - - -
84.7 - - - - 84.7 - - - - 84.7 - - - -
85.7 - - - - 85.7 - - - - 85.7 - - - -
85.6 - - - - 85.6 - - - - 85.6 - - - -
85.5 - - - - 85.5 - - - - 85.5 - - - -
85.4 G 61 178 183 85.4 S 68 298 317 85.4 G 62 402 433
85.3 L 62 179 184 85.3 T 69 299 318 85.3 S 63 403 434
85.2 Y 63 180 185 85.2 Y 70 300 319 85.2 F 64 404 435
85.1 S 64 181 186 85.1 R 71 301 320 85.1 F 65 405 436
E-STRAND 85 L 65 182 187 E-STRAND 85 V 72 302 321 E-STRAND 85 L 66 406 437
86 S 66 183 188 86 V 73 303 322 86 Y 67 407 438
87 S 67 184 189 87 S 74 304 323 87 S 68 408 439
88 V 68 185 190 88 V 75 305 324 88 K 69 409 440
89 V 69 186 191 89 L 76 306 325 89 L 70 410 441
90 T 70 187 192 90 T 77 307 326 90 T 71 411 442
91 V 71 188 193 91 V 78 308 327 91 V 72 412 443
92 P 72 189 194 92 L 79 309 328 92 D 73 413 444
93 S 73 190 195 93 H 80 310 329 93 K 74 414 445
94 S 74 191 196 94 Q 81 311 330 94 S 75 415 446
95 S 75 192 197 95 D 82 312 331 95 R 76 416 447
96 L 76 193 198 96 W 83 313 332 96 W 77 417 448
EF-TURN 96.1 - - - - EF-TURN 96.1 - - - - EF-TURN 96.1 - - - -
96.2 - - - - 96.2 - - - - 96.2 - - - -
F-STRAND 97 - - - - F-STRAND 97 L 84 314 333 F-STRAND 97 Q 78 418 449
98 G 77 194 199 98 N 85 315 334 98 Q 79 419 450
99 T 78 195 200 99 G 86 316 335 99 G 80 420 451
100 Q 79 196 203 100 K 87 317 336 100 N 81 421 452
101 T 80 197 205 101 E 88 318 337 101 V 82 422 453
102 Y 81 198 206 102 Y 89 319 338 102 F 83 423 454
103 I 82 199 207 103 K 90 320 339 103 S 84 424 455
104 C 83 200 208 104 C 91 321 340 104 C 85 425 456
FG-LOOP 105 N 84 201 209 FG-LOOP 105 K 92 322 341 FG-LOOP 105 S 86 426 457
106 V 85 202 210 106 V 93 323 342 106 V 87 427 458
107 N 86 203 211 107 S 94 324 343 107 M 88 428 459
108 H 87 204 212 108 N 95 325 344 108 H 89 429 460
109 K 88 205 213 109 K 96 326 345 109 E 90 430 461
110 P 89 206 214 110 A 97 327 346 110 A 91 431 462
111 - - - - 111 - - - - 111 - - - -
112 - - - - 112 - - - - 112 L 92 432 463
113 S 90 207 215 113 L 98 328 347 113 H 93 433 464
114 N 91 208 216 114 P 99 329 348 114 N 94 434 465
115 T 92 209 217 115 A 100 330 349 115 H 95 435 466
116 K 93 210 218 116 P 101 331 350 116 Y 96 436 467
117 V 94 211 219 117 I 102 332 351 117 T 97 437 468
G-STRAND 118 D 95 212 220 G-STRAND 118 E 103 333 352 G-STRAND 118 Q 98 438 469
119 K 96 213 221 119 K 104 334 353 119 K 99 439 470
120 K 97 214 222 120 T 105 335 354 120 S 100 440 471
121 V 98 215 223 121 I 106 336 355 121 L 101 441 472
122 - - - - 122 S 107 337 357 122 S 102 442 473
123 - - - - 123 K 108 338 358 123 L 103 443 474
124 - - - - 124 A 109 339 359 124 S 104 444 475
125 - - - - 125 K 110 340 360 125 P 105 445 476
126 - - - - 126 - - - - 126 - - - -
127 - - - - 127 - - - - 127 - - - -
128 - - - - 128 - - - - 128 - - - -
129 - - - - 129 - - - - 129 G CHS 106 446 477
130 - - - - 130 - - - - 130 K CHS 107 447 478

IMGT numbering
for the hinge		 IGHG1
amino acid
translation
J00228		 IMGT exon
numbering		 Eu
numbering
[1](4)		 Kabat
numbering
[2](4)
1 (E) 1 216 226
2 P 2 217 227
3 K 3 218 228
4 S 4 219 232
5 C 5 220 233
6 D 6 221 234
7 K 7 222 235
8 T 8 223 236
9 H 9 224 237
10 T 10 225 238
11 C 11 226 239
12 P 12 227 240
13 P 13 228 241
14 C 14 229 242
15 P 15 230 243

Correspondence between the IMGT unique numbering for the HINGE of Human IGHG2, IGHG3 and IGHG4

IMGT numbering
for the hinge		 IGHG2
amino acid
translation
J00230		 IMGT exon
numbering		 Eu
numbering
[1](4)		 Kabat
numbering
[2](4)
1 (E) 1 216 226
2 R 2 217 227
3 K 3 218 228
4 C 4 219 232
5 C 5 220 233
6 V 6 222 235
7 E 7 224 237
8 C 8 226 239
9 P 9 227 240
10 P 10 228 241
11 C 11 229 242
12 P 12 230 243

IMGT numbering
for the hinge		 H1 IMGT numbering
for the hinge		 IGHG3
amino acid
translation
X03604		 H2 H3 H4
IGHG3
amino acid
translation
X03604		 IMGT exon
numbering		 Eu
numbering
[1](4)		 Kabat
numbering
[2](4)		 IMGT exon
numbering		 Eu
numbering
[1]		 Kabat
numbering
[2]		 IMGT exon
numbering		 Eu
numbering
[1]		 Kabat
numbering
[2]		 IMGT exon
numbering		 Eu
numbering
[1]		 Kabat
numbering
[2]
1 (E) 1 216 226 1 (E) 1 - 241C 1 - 241R 1 - 241GG
2 L 2 217 227 2 P 2 - 241D 2 - 241S 2 - 241HH
3 K 3 218 228 3 K 3 - 241E 3 - 241T 3 - 241II
4 T 4 - 229 4 S 4 - 241F 4 - 241U 4 - 241JJ
5 P 5 - 230 5 C 5 - 241G 5 - 241V 5 - 241KK
6 L 6 219 232 6 D 6 - 241H 6 - 241W 6 - 241LL
7 G 7 220 233 7 T 7 - 241I 7 - 241X 7 - 241MM
8 D 8 221 234 8 P 8 - 241J 8 - 241Y 8 - 241NN
9 T 9 222 235 9 P 9 - 241K 9 - 241Z 9 - 241OO
10 T 10 223 236 10 P 10 - 241L 10 - 241AA 10 - 241PP
11 H 11 224 237 11 C 11 - 241M 11 - 241BB 11 - 241QQ
12 T 12 225 238 12 P 12 - 241N 12 - 241CC 12 - 241RR
13 C 13 226 239 13 R 13 - 241O 13 - 241DD 13 - 241SS
14 P 14 227 240 14 C 14 - 241P 14 - 241EE 14 229 242
15 R 15 228 241 15 P 15 - 241Q 15 - 241FF 15 230 243
16 C 16 - 241A 16 - - - - - - - - - -
17 P 17 - 241B 17 - - - - - - - - - -

IMGT numbering
for the hinge		 IGHG4
amino acid
translation
K01316		 IMGT exon
numbering		 Eu
numbering
[1]		 Kabat
numbering
[2]
1 (E) 1 216 226
2 S 2 217 227
3 K 3 218 228
4 Y 4 - 229
5 G 5 - 230
6 P 6 224 237
7 P 7 225 238
8 C 8 226 239
9 P 9 227 240
10 S 10 228 241
11 C 11 229 242
12 P 12 230 243
IMGT notes:
(1) J00228 corresponds to the IGHG1*01 allele (Alignment of alleles: Human IGHG1) and to a G1m1,17 chain (G1m allotypes). The Eu gamma1 chain is encoded by the IGHG1*03 allele (CH1 K120>R, CH3 D12>E and L14>M) and is a G1m3 chain (G1m allotypes).
(2) The IGHG1, IGHG3 and IGHG4 CH2 exons encode 110 amino acids. The IGHG2 CH2 exon encodes 109 amino acids, due to a 3 nt deletion corresponding to codon 3 (position 1.4 in the IMGT unique numbering for C-DOMAIN).
(3) The last two amino acids of the IGHG CH3 exons belong to the CHS which encodes the heavy chain C-terminus found in the secreted immunoglobulins.
(4) In Kabat [2], Eu index from 219 to 221 should have been aligned with the Eu protein (pp. 671). As a consequence, Kabat positions 232, 233 and 234 correspond to Eu index positions 219, 220 and 221, respectively (pp. 670-678).
(5) IMGT labels (concepts of description) are written in capital letters.
References:
[1] Edelman, G.M. et al., Proc. Natl. Acad. USA, 63, 78-85 (1969). PMID: 5257969
[2] Kabat, E.A. et al., Sequences of proteins of immunological interest. 5th Edition - US Department of Health and Human Services, NIH publication n° 91-3242, pp 662,680,689 (1991).