Dorothy G.Rainey;75;of Denbo;died Monday;May 10;1993;at 12:35 a.m.in Mon Valley Hospital;Carroll Township.  She was born July 10;1917;in Belle Vernon;a daughter of the late Harry and Elizabeth Turnbull Sethman.  Mrs.Rainey had lived in Denbo for the past 25 years and was formerly of Belle Vernon.  She is survived by a son;Ronald Rainey of Denbo;two daughters;Mrs.LeRoy (Henrietta) Bair of Hiller and Mrs.Michael (Darlene) Skobel of Belle Vernon;two brothers;Harry Sethman Jr.of Belle Vernon and Howard Sethman of LaMarada;Calif.;four sisters;Ethel Venneri and Hannah Bennett;both of Belle Vernon;Martha Warner of Springfield;Ohio and Florence Carlametti of Belle Vernon and eight grandchildren.  In addition to her parents;she was preceded in death by her husband;Edwin J.Rainey;Sept.8;1977;a brother;Richard Sethman;and two sisters;Margaret Carr and Norma Jean Seibert.  Friends will be received Monday from 7 to 9 p.m.and Tuesday from 2 to 4 and 7 to 9 p.m. at the Ferguson Funeral Home Inc.;700 Broad Ave.;Belle Vernon.  A service will be held in the funeral home Wednesday at 11 a.m.with the Rev.Dr.Thomas St.Clair of the First United Methodist  Church officiating.  Interment will follow in Belle Vernon Cemetery.  The Ferguson Funeral Home Inc.;700 Broad Ave.;Belle Vernon;is in charge of the arrangements.