Treatment solution for preparing sample solution for nucleic acid amplification reaction and method for detecting nucleic acid by using treatment solution

A method for amplifying a target nucleic acid, without purifying nucleic acid, contained in a tissue derived from a living body, comprising the steps of:

• preparing a first sample solution without purifying nucleic acid by homogenizing a tissue derived from a living body in a treatment solution containing dimethyl sulfoxide, a surfactant and water and by removing solid materials in the solution rendered homogenous, the first sample solution containing nucleic acid which is transferred from the tissue;
• preparing a second sample solution without purifying nucleic acid by mixing the first sample solution, deoxyribonucleotide triphosphates, a DNA polymerase and a primer which is complementary to the target nucleic acid;
• and
• amplifying the target nucleic acid contained in the second sample solution prepared without purifying nucleic acid;
• wherein the pH of the treatment solution is 2.5 to 5.0, and the concentration of dimethyl sulfoxide contained in the treatment solution for reducing the influence of an inhibitor during the target nucleic acid amplification is 5 to 30% (v/v).