- VernacularTitle:PCR-RFLP法在脊髓性肌萎缩症基因检测中的局限性
- Author:
Yu-wei JIN
1
;
Yu-jin QU
;
Hong WANG
;
Jin-li BAI
;
Fang SONG
Author Information
- Publication Type:Journal Article
- MeSH: Exons; Humans; Muscular Atrophy, Spinal; genetics; Mutation; Polymerase Chain Reaction; methods; Polymorphism, Restriction Fragment Length
- From: Chinese Journal of Medical Genetics 2012;29(1):34-37
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo explore the applicability and limitation of PCR-restriction fragment length polymorphism (PCR-RFLP) method for genetic diagnosis of spinal muscular atrophy (SMA).
METHODSPCR-RFLP was applied to detect potential deletion in exons 7 and 8 of SMN1 gene in 935 suspected cases with SMA. Multiplex ligation-dependent probe amplification(MLPA) was carried out to analyze dosage alteration of SMN1 gene in 339 of such cases. To confirm the accuracy of PCR-RFLP method for homozygous and heterozygous deletions detection, the consistency of PCR-RFLP and MLPA results were assessed with a Pearson Chi-square test.
RESULTSHomozygous deletion of exon 7 of SMN1 was detected in 590 suspected cases. The rate of diagnosis was therefore 63.1% (590/935). For the 339 suspected cases, PCR-RFLP and MLPA respectively identified 194 and 196 homozygous deletions in the exon 7 of SMN1 gene, suggesting a good consistency (98.9%)(Chi-square = 0.2, P = 0.88). However, only 4 of 339 cases was found to carry a heterozygous deletion of SMN1 exon 7 by PCR-RFLP, in contrast with 17 detected by MLPA. The consistency only reached 23.5%, for which statistical significance was detected (Chi-square = 8.29, P< 0.01).
CONCLUSIONAlthough PCR-RFLP is a simple, specific and efficient method for SMA diagnosis, it has obvious limitation for the diagnosis of 5%-10% SMA patients who have carried a compound heterozygous mutation.