Seriously, DNA from a prostitute's clothing????
There are a few threads on this "revelation" starting at the end of last week.
I was much more impressed with an effort a few years ago to recover DNA from the stamp on a probable actual Ripper letter.
(As opposed to the hoax and "Let's keep the story going to sell more papers" efforts by "reporters" and editors.
I've posted a link on this thread to a different article from the Daily Mail. The item of clothing was a shawl left at the scene. The guy who bought it didn't think it belonged to Eddowes because she was so poor she had pawned her shoes the day before she died. He believes that the shawl was left at the scene by the killer. They tested blood spatter and what they believe was sperm found on the shawl. The article said they were able to extract six complete DNA samples from the shawl. The samples were compared to blood samples from Eddowes' 3rd great-granddaughter, and a British descendant of Kosminkski's sister. The testing was conducted over a three year period.