Could I have a statement, please? <a href=" http://www.tamingtwins.com/where-can-i-buy-tretinoin-uk.pdf#restoration ">buy tretinoin</a> "It's great to see large-scale sequencing being applied to the Y chromosome," says Chris Tyler-Smith, who studies genetics and human evolution with the U.K.'s Wellcome Trust. "I think this is the future of Y chromosome study."