Molecular characterization and copy number of SMN1, SMN2 and NAIP in Chinese patients with spinal muscular atrophy and unrelated healthy controls

Table 4 Copy numbers of SMA-related genes in 212 Chinese healthy individuals determined by MLPA

		Total	Gene copy number
Pattern	Group	N = 212	NormalSMN1gene	NormalSMN2gene	NormalNAIPgene	HybridSMNgene	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.

ISSN: 1471-2474