Table 4.
Copy numbers of SMA-related genes in 212 Chinese healthy individuals determined by MLPA
| Total | Gene copy number | ||||||
|---|---|---|---|---|---|---|---|
| Pattern | Group | N = 212 | Normal SMN1 gene | Normal SMN2 gene | Normal NAIP gene | Hybrid SMN gene | Gene lacking partial sequences |
| A | 1 | 117(55.2%) | 2 | 2 | 2 | 0 | 0 |
| B | 2 | 1(0.5%) | 2 | 1 | 2 | 1 e | 0 |
| C | 3 | 1(0.5%) | 1 | 2 | 2 | 1 h | 0 |
| D | 4 | 54(25.5%) | 2 | 1 | 2 | 0 | 0 |
| E | 5 | 1(0.5%) | 2 | 0 | 2 | 1 e | 0 |
| F | 6/7 | 8(3.8%) | 2 | 1 | 2 | 0 | 1 g |
| G | 8/9 | 9(4.2%) | 2 | 0 | 1 | 0 | 1 g |
| H | 10 | 1(0.5%) | 2 | 1 | 1 | 0 | 0 |
| I | 11 | 5(2.3%) | 2 | 2 | 2 | 0 | 1 g |
| J | 12 | 1(0.5%) | 1 | 2 | 2 | 1 h | 1 g |
| K | 13 | 2(0.9%) | 2 | 1 | 2 | 1 e | 1 g |
| L | 14 | 2(0.9%) | 3 | 1 | 2 | 0 | 0 |
| M | 15 | 3(1.4%) | 2 | 2 | 1 | 0 | 1 a |
| N | 16 | 2(0.9%) | 2 | 3 | 2 | 0 | 0 |
| O | 17 | 1(0.5%) | 1 | 1 | 2 | 0 | 1 b and 1 c |
| P | 18 | 1(0.5%) | 3 | 2 | 2 | 0 | 1 g |
| Q | 19 | 1(0.5%) | 3 | 2 | 1 | 0 | 1 a |
| R | 20 | 1(0.5%) | 1 | 2 | 1 | 0 | 1 a |
| S | 21 | 1(0.5%) | 3 | 1 | 2 | 0 | 1 g |
a:NAIP gene lacking exon 5, b:SMN1 gene lacking exon 7, c:SMN2 gene lacking exon 7, e:Hybrid SMN gene in which exon 8 of SMN2 was converted to exon 8 of SMN1, g:NAIP gene lacking exon13, h:Hybrid SMN gene in which exon 8 of SMN1 was converted to exon 8 of SMN2.