From: Mutation analysis of 419 family and prenatal diagnosis of 339 cases of spinal muscular atrophy in China
Clinical types
Type I
Type II
Type III
Type IV
Total
0
168 (40.10%)
121 (28.88%)
99 (23.63%)
16 (3.82%)
404 (96.42%)
≥1
9 (2.18%)
5 (1.19%)
1 (0.24%)
0 (0.00%)
15 (3.58%)
177 (42.24%)
126 (30.07%)
100 (23.87%)
419 (100.00%)