RT-PCR analysis of RMS biopsies with primers specific for the PAX3/FKHR gene fusion product, MyoD1 and α/γAChR. Lane 1 = 10162/97,AR; lane 2 = 15378/89,AR; lane 3 = 17940/94,AR; lane 4 = 14097/90,AR; lane 5 = 5750/93,AR; lane 6 = 11421/89,AR; lane 7 = 32931/88,AR; lane 8 = 18471/96,AR; lane 9 = 7547/90,ER; lane 10 = 18325/95,ER; lane 11 = 25923/95,ER; lane 12 = 11563/92,ER; lane 13 = 17285/90,ER; lane 14 = 11279/87,ER; lane 15 = 7863/95,ER; lane 16 = 3207/93,ER. AR, alveolar RMS; ER, embryonal RMS.