Development of a nylon membrane chip for rapid detecting the diabetes-associated 45 mutant loci in mitochondrial DNA / 中华检验医学杂志

ABSTRACT

Objective To develop a nylon membrane chip for rapid and systematic detection of the diabetes-associated 45 mutant loci in mitochondrial DNA(mtDNA).Methods The mutant-and wild-type probes were designed for detection of 45 mutant loci in mtDNA with Primer Premier 5.0 and NCBI BLAST softwares and the 90 probes with 8 poly T were immobilized on the Hybond N~+ nylon membranes which were treated with 5?SSC Buffer by UV-crosslinking;Then asymmetric PCR was employed to obtain the target single strand DNA(ssDNA).The PCR products were labeled with biotin after purification.NBT/BCIP was used as substrate that yields a very intense purple signal followed by AP-avidin,and the signals were observed in 24 samples with known sequences to evaluate the chips,each sample was repeatedly measured three times.Results The specific target fragments of 45 loci can be amplified under the same condition with nine sets of primers.The annealing temperatures of the wild-type [(59.01?1.42)℃] and mutant-type [(59.34?1.29)℃ ] probes are so close(t=1.046,P =0.301)that hybridization can be performed at the same temperature.The spots on the membrane chip are distinct,regular and well-distributed.The results of positive-and negative-control are perfect.The signals of negative probes and the background are similar.The results of chip were nearly concordant with that of DNA sequences(?~2=113.132,Kappa value =0.888,P = 0.000)except for T16189C mutant.Conclusions We have successfully developed a nylon membrane chip for rapid and systematic detection of the diabetes-associated 44 mutant loci in mtDNA.It could be used for screening for diabetic patients and high-risk people.