when this derivative der ( x ) , t ( x ; 14 ) ( xqter leads to xp22 : :14q21 leads to 14qter ) chromosome carrying the human gene for hypoxanthine-guanine phosphoribosyltransferase was selected for and against in cell hybrid lines by the appropriate selective conditions , the human tryptophanyl-trna synthetase activity was found to segregate concordantly .
C1520175
xp22
C0008633
chromosome