Comprehensive scanning of the ATM gene with DOVAM-S.
Mutation detection at the ATM locus has been difficult because of the large size of the gene (66 exons), the fact that mutations are located throughout the entire gene with no hotspots, and the difficulty of distinguishing mutations from polymorphisms. In this study, the entire coding region (exons 4-65) was scanned, as well as the adjacent intronic regions, using DOVAM-S (Detection Of Virtually All Mutations-SSCP), a robotically-enhanced, multiplexed scanning method that is a highly sensitive modification of SSCP. Forty-three unrelated patients and four obligate carriers were studied. Of the 90 expected mutant alleles, 71 were identified (79%). The mutations included 17 nonsense (24%), 20 frameshift (28%), 20 splice (28%), 10 missense (14%), one in-frame deletion (1%), and three that alter the initiation codon (4%). Among the ataxia-telangiectasia patients, two potentially causative mutations were identified in 30 individuals: 22 had two truncating mutations, four had one truncating and one missense mutation, three had two missense mutations, and one had a truncating mutation and an in-frame deletion of three amino acids. For seven A-T patients and all four obligate carriers, only one truncating mutation was detected. Six of the 43 A-T patients had no detected mutations (14%). Twelve novel mutations and six novel polymorphisms were detected. The results of this complete scan of the ATM coding region showed that 86% of causative ATM mutations were truncating and 14% were missense. DOVAM-S is a rapid, efficient method of performing A-T diagnosis and carrier testing on a clinical time scale.
Buzin
Carolyn H
CH
Department of Molecular Genetics, City of Hope National Medical Center, Duarte, California 91010-3000, USA.
Gatti
Richard A
RA
Nguyen
Vu Q
VQ
Wen
Cindy Y
CY
Mitui
Midori
M
Sanal
Ozden
O
Chen
Jie Sheng
JS
Nozari
Guity
G
Mengos
April
A
Li
Xuemin
X
Fujimura
Frank
F
Sommer
Steve S
SS
D000293:Adolescent; D000328:Adult; D000818:Animals; D001260:Ataxia Telangiectasia / Q000201:enzymology / Q000235:genetics; D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis / Q000379:methods; D004268:DNA-Binding Proteins; D005091:Exons / Q000235:genetics; D006580:Genetic Carrier Screening / Q000379:methods; D006801:Humans; D008297:Male; D009154:Mutation / Q000235:genetics*; D018807:Polymorphism, Single-Stranded Conformational; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D012371:Robotics / Q000379:methods; D025521:Tumor Suppressor Proteins; D029867:Xenopus Proteins; D014982:Xenopus laevis / Q000235:genetics
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D025521:Tumor Suppressor Proteins; D029867:Xenopus Proteins; C576898:Atr protein, Xenopus; C576324:ATM protein, human; C576597:ATR protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases