licked by the writer of one of the supposed Ripper letters analysed for DNA, and claimed it pointed to Sickert. However, the analysis could only be of Mitochondrial DNA, and the result could be shared by anything from between 1 percent and 10 percent of the population.<ref>[https://www.jack-the-ripper.org/walter-sickert.htm "Patricia Cornwell wades in", Jack the Ripper 1888]</ref> Sickert was, at best, "not excluded" by the analysis, but his typically European result would be shared by large groups of Britons alive in 1888. Cornwell has said, including in her Desert Island Discs interview with Sue Lawley, that new evidence has come to light since 2002. She states that a paper manufacture expert she hired asserts that reams of paper supposedly used by Jack the Ripper to write several letters to Scotland Yard and paper purchased by Sickert's mother bear the same small-press watermark. She also claims that there are matches in the cutter's marks, which are a result of the rough cutting of each quire (or small package) for packaging. A "quire" was usually of 24 sheets. Responses from critics Though Cornwell's book sold many copies, many Ripperologists and other critics argued that Cornwell's theory was far from persuasive. Critics point out that most, if not all, of the Ripper letters are considered hoaxes by other authorities and that if they really are hoaxes, then Sickert may have been one of the hoaxers. Thus, even if he did write one or more of these letters, that does not prove that he was the Ripper. The evidence she claims supports the idea that Sickert had a disfigured penis also supports the more accepted theory that he had a fistula in his anus. Details in the letters and supposedly seen in the paintings she claims only the killer would know had previously been published in newspapers and a book released in France. Sickert could have easily got hold of the book in question, as he also lived in France off and on. In fact, evidence shows that he was probably in France on the nights of four of the five Ripper murders. Critics also note that Cornwell has said that she did not have a theory about the murders until about a year before her book was published and believed that the first suspect mentioned to her was the one who really committed the crimes. In September 2014, Finnish molecular biologist Jari Louhelainen claimed that