Table 2.
Common POLG mutations. The three most commonly reported POLG mutations, p.A467T, p.W748S and p.G848S, have been reported in all possible compound heterozygous combinations, as well as in homozygous form. Heterozygous case reports are rare for p.A467T and p.W748S, and there are none for p.G484S. Comparatively, p.G848S appears to occur in more severe cases, and p.W748S consistently shows a slightly milder phenotype in comparison to p.A467T.
| Mutation | Clusters | Average age of onset (years) |
Standard deviation | Number of reported cases |
|---|---|---|---|---|
| W748S + E1143G/wt | 5 + SNP/– | 59.0 | 4.0 | 2 (1 outliera) |
| A467T/wt | 2/– | 42.8 | 11.2 | 5 (1 outlierb) |
| W748S/W748S | 5/5 | 21.4 | 10.4 | 27 (1 outlierc) |
| W748S + E1143G/W748S + E1143G | 5 + SNP/5 + SNP | 22.1 | 11.1 | 35 |
| A467T/A467T | 2/2 | 19.9 | 13.7 | 45 |
| G848S/G848S | 1/1 | 5.0 | 0.0 | 1 |
| W748S/A467T | 5/2 | 28.7 | 11.2 | 27 |
| W748S + E1143G/A467T | 5 + SNP/2 | 21.4 | 11.7 | 15 |
| A467T/W748S + K561M | 2/5 + 2 | 0.01 | 0.0 | 1 |
| A467T/G848S | 2/1 | 1.7 | 2.0 | 22 |
| W748S/G848S | 5/1 | 5.7 | 2.6 | 8 |
| A467T/PNF | 2/– | 1.5 | 1.0 | 14 (1 outlierd) |
| W748S/PNF | 5/– | 1.7 | 1.3 | 5 |
| W748S + Q497H + E1143G/ W748S + Q497H + E1143G |
5 + 2 + SNP/5 + 2 + SNP | 19.0 | 4.0 | 2 |
| W748S + Q497H + E1143G/A467T | 5 + 2 + SNP/2 | 17.0 | 0.0 | 1 |
Sarzi et al. [47], patient 36 (id: 404). [http://www.ncbi.nlm.nih.gov/pubmed/17452231].
Galassi et al. [48], (id: 409). [http://www.ncbi.nlm.nih.gov/pubmed/18504126].
Tzoulis et al. [49], (id: 552). [http://www.ncbi.nlm.nih.gov/pubmed/24841123].
Martikainen et al. [50], (id: 666). [http://www.ncbi.nlm.nih.gov/pubmed/27111573].