I may be repeat infromation posted earlier, but according to an 2002 FBI report, it may not be possible to obtain a DNA profile using STR (short Tandem Repeat) on old or degrade blood or semen samples. The report suggests mtDNA (mitochondrial) can be used on very hair or bone samples, but were any taken that could be from the perpetrator at the 1961 body site? But DNA is advancing.