When the Wind Blows

Quoting from author's website: "Young and talented veterinarian living in Colorado plagued by the mysterious murder of her husband" meets "a troubled and unconventional FBI agent", "stumbles upon a strange, astonishing phenomenon that will change the course of her life forever...." (number of dots sic) and "uncover[s] one of the most diabolical and inhuman plots of modern science": i. e. genetically engineered children with wings on the run from Eeevil Authorities.