blue eyes Live Science/Jeanna Bryner blue eyes genetic difference was traced back to the maternal lineage arose about 10,000 years ago in Europe having blue eyes gene mutation for blue eyes gene mutation for blue eyes blue eyes traced back to a single individual blue eyes light-colored eyes a hunt for long haplotypes una mutazione genetica gene mutation for blue eyes One Common Ancestor Behind Blue Eyes mutation génétique Blue eyes originally spread from one individual One Common Ancestor Behind Blue Eyes blue eyes genetic mutation responsible for blue eyes Live Science/Jeanna Bryner genetic difference was traced back to the maternal lineage genetic difference was traced back to the maternal lineage blue eyes livescience.com