DNA analysis provides evidence that Jack the Ripper's true identity was Aaron Kosminski! At the time of the killings, Mr. Kosminski was a 23-year-old barber living in Hastings, London. He was also a prime police suspect in the killers during the initial investigation in 1888 and also by forensic investigators throughout history.
This new genetic analysis of Jack the Ripper's DNA data was performed by Dr. Jari Louhelainen and Dr. David Miller, scientists at the University of Leeds in the United Kingdom and was published in the Journal of Forensic Sciences in March 2019.
The scientists sequenced the mitochondrial DNA from blood and semen found on the shawl of the Ripper's fourth victim and compared the genetic sequence to DNA samples taken from living descendants of Catherine Eddowes (the victim) and Aaron Kosminski (a prime suspect).
The DNA matched that of Mr. Kosminski's descendants, providing very strong evidence that the killer was Mr. Kosminski.
Below is a sketch of Aaron Kosminski aka Jack the Ripper.
Interesting in learning more? A great summary of the forensic DNA sequencing study was published in the journal Science.