Quantitative studies on SMN1 gene and carrier testing of spinal muscular atrophy
10.3760/j.issn:1003-9406.2005.06.001
- VernacularTitle:脊髓性肌萎缩症SMN1基因定量研究及基因携带者的筛查
- Author:
Wan-Jin CHEN
1
;
Zhi-Ying WU
;
Ning WANG
;
Min-Ting LIN
;
Shen-Xing MU-RONG
Author Information
1. 福建医科大学附属第一医院
- Keywords:
spinal muscular atrophy;
real-time fluorescence quantitative PCR;
genetic counseling
- From:
Chinese Journal of Medical Genetics
2005;22(6):599-602
- CountryChina
- Language:Chinese
-
Abstract:
Objective To construct a method for detecting the copy number of survival of motor neuron 1 gene ( SMN1 ) with single copy difference based on real-time fluorescence quantitative PCR, and to make practical use of the method for acquiring the data on SMN1 copy number in Chinese as well as for screening the carriers of spinal muscular atrophy (SMA) from healthy individuals and SMA families. Methods Exon 7 and flanking area of SMN1 gene were amplified by real-time fluorescence quantitative PCR in 264 healthy individuals, in 1 standard sample having 2 SMN1 but having no SMN2 , and in 88 parents of SMA patients. The samples for detecting were diluted to 30 ng/μL and the standard sample was diluted to 15 ng/μL, 30 ng/μL, 45 ng/μL, 60 ng/μL; the unknown samples and 4 standard samples with different concentrations were amplified at the same time, a standard curve could be drawn out according to the results of the 4 standard samples, then the copy number of samples could be calculated. Results Of 88 parents' samples, 84samples each had 1 copy of SMN1 , and the rest 4 each had 2 copies of SMN1 . Of 264 healthy individuals' samples,5 samples each had only 1 copy of SMN1 (an indicator of definite gene carriers), 232 samples each had 2 copies of SMN1 , 25 samples each had 3 copies of SMN1 , and 2 samples each had 4 copies of SMN1 . Of the samples of 32members of SMA families, 2 samples each had only 1 copy of SMN1 indicating definite gene carriers, 25 samples each had 2 copies ofSMN1 , and 5 samples each had 3 copies ofSMN1 . Conclusion SMN1 copy number could be detected precisely by real-time fluorescence quantitative PCR; the screening of gene carriers could provide essential data for genetic counseling.
