DNA-probes for the highly sensitive identification of single nucleotide polymorphism using single-molecule...

Area of Science:

• Molecular Biology
• Biochemistry
• Analytical Chemistry

Background:

• Accurate identification of single nucleotide polymorphisms (SNPs) is crucial for genetic research and diagnostics.
• Existing methods for SNP detection can be limited in sensitivity or require complex sample preparation.

Purpose of the Study:

• To develop a highly sensitive and specific method for SNP identification in homogeneous solutions.
• To utilize fluorescence single-molecule spectroscopy with novel hairpin probes for enhanced detection.

Main Methods:

• Employing fluorescently labeled hairpin-structured oligonucleotides (smart probes) that exhibit a change in fluorescence upon target hybridization.
• Utilizing time-resolved single-molecule fluorescence spectroscopy to detect individual probe events.
• Implementing unlabeled blocking oligonucleotides to ensure specificity against mismatched sequences.

Main Results:

• Demonstrated significant fluorescence intensity increase upon hybridization to target SNP sequences.
• Achieved high specificity by effectively blocking probes with mismatched sequences.
• Reached subnanomolar sensitivity, enabling detection of individual DNA molecules.

Conclusions:

• The developed smart probe and single-molecule spectroscopy method provides a highly sensitive and specific approach for SNP identification.
• This technique offers a powerful tool for genetic analysis and molecular diagnostics.