Detection of human genomic mutations by chemical single-reaction DNA sequencing

One‐Pot TiO2‐Catalyzed Synthesis of Nucleic Bases and Acyclonucleosides from Formamide: Implications for the Origin of Life

“…A > C > T). [14,15] The poly-G and poly-A degradations are not enhanced by low concentrations of TiO 2 ; both poly-G and poly-A are actually digested to a lesser extent at higher concentrations. Degradation of poly-C is enhanced by TiO 2 only at high concentration, while a major enhancement effect on poly-T is observed between 0.6 and 3 mg mL À1 which causes an essentially complete and regular digestion of the homogenous sequence tract.…”

“…The degradation pathway of nucleosides in the formamide ± TiO 2 system was analyzed for 2'-deoxyadenosine (12), 2'-deoxyguanosine (13), 2'-deoxycytidine (14), and thymidine (15). [11] The nucleoside (1.0 mmol) was added to formamide (5 mL) in the presence of 2 % w/w TiO 2 and the mixture was heated at 160 8C for 2 days.…”

“…[14,15] Figure 4 compares the sensitivity of the four bases to hot formamide as a function of the concentration of TiO 2 . For both homo-and heterogeneous oligonucleotides, the degradation conditions used in this assay cause less than one hit per molecule, as shown by the regularity of the cleavage patterns and by the presence of a substantial amount of unreacted molecules.…”

“…[13] This reaction pattern is the basis for novel chemical DNA sequencing procedures. [14,15] Thus, to evaluate the prebiotic relevance of any formamidebased synthesis of nucleic acid precursors, the study of the degradative pathway under similar experimental conditions is necessary. Here we describe the unprecedented one-pot TiO 2 -catalyzed synthesis of nucleobases, N 9 -formylpurines, and acyclonucleosides from formamide.…”

Mechanism of degradation of 2′-deoxycytidine by formamide: Implications for chemical DNA sequencing procedures

“…8-u This property and the possibility of analyzing several differently labeled samples in the same lane offers the possibility of accurate comparative familial analyses. 13 The reliability of the analysis is based on the possibility of unambiguous discrimination among the four signals. The order of sensitivity observed in the formamide reaction is G>A>C>T, where the reactivity ratio G/A ranges from 1 to 1.5 depending on the reaction conditions; the reactivity ratio C/A is 0.15, and that one T/C is between 0.7 and 0.5.…”