title: [Application of MALDI-TOF-MS in gene testing for non-syndromic hearing loss].
abstract: OBJECTIVE
  To investigate the feasibility of Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) , according to the genetic test of non-syndromic hearing loss (NSHL), and check using the direct sequencing.
  
  
  METHODS
  Peripheral blood was collected from 454 NSHL patients. DNA samples were extracted and 20 loci of the four common disease-causing genes were analysed by MALDI-TOF-MS, including GJB2 (35delG, 167delT, 176_191del16, 235delC, 299_300delAT ), GJB3 (538C→T, 547G→A), SLC26A4 (281C→T, 589G→A, IVS7-2A→G, 1174A→T, 1226G→A, 1229C→T, IVS15+5G→A, 1975G→C, 2027T→A, 2162C→T, 2168A→G), and mitochondrial 12S rRNA (1494C→T, 1555A→G). Direct sequencing was also used to analyse the aforementioned 20 loci in order to validate the accuracy of MALDI-TOF-MS.
  
  
  RESULTS
  Among the 454 patients, 166 cases (36.56%) of disease-causing mutations were detected, which included 69 cases (21.15%) of GJB2 gene mutation, four cases (0.88%) of GJB3 gene mutation, 64 cases (14.10%) of SLC26A4 gene mutation, and three cases (0.66%) of mitochondrial 12S rRNA gene mutation. Moreover, the results obtained from direct sequencing and MALDI-TOF-MS were consistent, and the results showed that the two methods were consistent.
  
  
  CONCLUSIONS
  The MALDI-TOF-MS detection method was designed based on the hearing loss-related mutation hotspots seen in the Chinese population, and it has a high detection rate for NSHL related mutations. In comparison to the conventional detection methods, MALDI-TOF-MS has the following advantages: more detection sites, greater coverage, accurate, high throughput and low cost. Therefore, this method is capable of satisfying the needs of clinical detection for hearing impairment and it is suitable for large-scale implementation.
authors: BGI Clinical Laboratories (Shenzhen), Shenzhen 518083, China. Email: zengyun@genomics.cn.
authors: Yun
authors: Y
authors: Zeng
authors: BGI Clinical Laboratories (Shenzhen), Shenzhen 518083, China.
authors: Dan
authors: D
authors: Jiang
authors: Da-fei
authors: DF
authors: Feng
authors: Dong-dong
authors: DD
authors: Jin
authors: Xiao-hui
authors: XH
authors: Wu
authors: Yan-li
authors: YL
authors: Ding
authors: Jing
authors: J
authors: Zou
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D017630:Connexins; D003638:Deafness / Q000235:genetics; D005260:Female; D005820:Genetic Testing; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D055815:Young Adult
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26