Table 4.
Characteristics of TLR2 mutations observed in white subjects with systemic meningococcal disease (n = 102 individuals and 187.2 CE examined) and normal controls (n = 104 individuals and 142.7 CE examined)
| Number of chromosomes | Nucleotide (genomic) | Amino acid | Receptor domain* | Allele frequency† | P‡ |
|---|---|---|---|---|---|
| Meningococcal disease | |||||
| 105§ | 726 C → T | None | — | 0.5198 | 0.533 |
| 1 | 768 G → C | None | — | 0.0050 | 1.000 |
| 15 | 1479 T → C | None | — | 0.0773 | 0.388 |
| 13 | 1752 C → T | None | — | 0.0663 | 0.023 |
| 2 | 1818 G → A | None | — | 0.0102 | 0.500 |
| 2 | 2021 C → A | P631H | Cytoplasmic | 0.0104 | 0.050 |
| 6 | 2387 G → A | R753Q | Cytoplasmic | 0.0313 | 1.000 |
| Controls | |||||
| 94 | 726 C → T | None | — | 0.5529 | |
| 8 | 1479 T → C | None | — | 0.0506 | |
| 3 | 1752 C → T | None | — | 0.0174 | |
| 8 | 2021 C → A | P631H | Cytoplasmic | 0.0476 | |
| 5 | 2387 G → A | R753Q | Cytoplasmic | 0.0329 | |
The human TLR2 protein is 784 aa in length. Residues 1–588 are designated here as the ectodomain, residues 589–615 are assumed to span the plasma membrane, and residues 616–784 are considered to comprise the cytoplasmic domain.
Allele frequencies refer to the number of observations divided by the number of loci that could be examined at the site in question. All coding mutations occurred in isolation from one another; i.e., no compound heterozygotes were observed.
P value refers to the likelihood (two-sided; Fisher's exact test) that the difference between the incidence of each variant allele in the meningococcal and control populations would occur by chance.
The ratio of T/T:C/T:C/C individuals among the meningococcal population was (32:30:23), whereas the ratio of T/T:C/T:C/C individuals among the control population is (25:55:21). Neither distribution represents a significant departure from predictions of the Hardy–Weinberg equilibrium.