Table 2. GAA polymorphisms in Italian population.
| Location | Single base change§ | Protein Sequence | Frequency* |
| Exon 2 | c.271GA c.324TC |
p.D91N p.C108C |
0.6% 28% |
| Intron 2 | c.547-4CG c.547-39TG |
Non coding Non coding |
31% 25% |
| Exon 3 | c.596GA c.642CT c.668AG |
p.H199R p.S214S p.H223R |
42% 18% 44% |
| Intron 4 | c.854ins7nt + 7 c.858 + 29TC |
Non coding Non coding |
32% 15% |
| Exon 5 | c.921AT | p.A307A | 5.4% |
| Intron 5 | c.955 + 12 AG | Non coding | 33% |
| Exon 8 | c.1203AG | p.Q401Q | 3.9% |
| Intron 8 | c.1327-18GA | Non coding | 35% |
| Exon 9 | c.1374CT | p.Y458Y | 5.1% |
| Intron 9 | c.1438-19CG | Non coding | 42% |
| Exon 11 | c.1581GA | p.R527R | 32% |
| Intron 12 | c.1754 + 12GA | Non coding | 24% |
| Exon 13 | c.1830CT | p.A610A | 11% |
| Intron 14 | c.2040 + 20AG | Non coding | 36% |
| Exon 15 | c.2133AG c.2154TC |
p.T711T p.V718V |
15% 35% |
| Intron 15 | c.2190-13GT | Non coding | 40% |
| Exon 16 | c.2238GC | p.W746C | 10% |
| Intron 16 | c.2331 + 20GA | Non coding | 38% |
| Exon 17 | c.2338AG | p.I780V | 42% |
| Exon 18 | c.2553GA | p.G851G | 40% |
| Exon 20 | c.3082CT c.3277TC |
Non coding Non coding |
24% 30% |
For cDNA numbering + 1 corresponds to the A of the first ATG translation initiation codon (cDNA reference sequence Y00839.1). § New polymorphisms are indicated in bold. * Frequency is calculated on 100 normal alleles