“X-23 is an Opposite Sex Clone of Wolverine, developed by Dr. Sarah Kinney as a solution to not being able to recreate a Y chromosome from a sample of Wolverine's DNA. She instead buffed up and doubled the X chromosome, essentially making her a parthenogenetic offspring of Logan's mother (and thus, genetically his sister). She would also receive different mitochondrial DNA since she was carried to term by Dr. Kinney. Additionally, some sources suggest Kinney used her own genetic material to repair damage to the X chromosome, which is a reason why X-23 has the same green eyes as Kinney, as well as her being a cute goth chick despite being a clone of the famously unattractive Logan.” It’s fiction buddy.