Table 7. Type 1 diabetes associated polymorphic residues of DQA1 alleles with a proposed function.
| DQA1 allele | Amino Acid position | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| CD4 | ||||||||||
| TCR | HB | HH | ||||||||
| P6 | P1 | P6 | P6/9 | P9 | ||||||
| 11 | 52 | 55 | 61 | 64 | 66 | 69 | 76 | 129 | 175 | |
| Susceptibility alleles | ||||||||||
| 03:01 | Y | R | R | F | T | I | L | V | H | E |
| 05:01 | Y | R | R | F | T | I | L | L | H | K |
| Protective alleles | ||||||||||
| 01:01 | C | S | G | G | R | M | A | M | Q | Q |
| 01:02 | C | S | G | G | R | M | A | M | Q | Q |
| 01:03 | C | S | G | G | R | M | A | M | H | Q |
Positions identified in bold show amino acids that are exclusive to the type 1 diabetes susceptibility or protective alleles. The function associated with each amino acid is depicted on top. P; pocket (peptide binding), HH; homodimer of heterodimer, HB; hydrogen bond to peptide, TCR; T-cell receptor contact site to HLA molecule, CD4; site of contact of HLA molecule to CD4.