N-myc gene is amplified in alveolar rhabdomyosarcomas (RMS) but not in embryonal RMS.

DNA from 13 (6 alveolar and 7 embryonal) childhood rhabdomyosarcomas (RMS) was examined to determine the incidence and prognostic relevance of N- and c-myc genes. Southern analysis showed 5- to 20-fold amplification of N-myc gene in 4 of 6 alveolar but in none of 7 embryonal RMS (p less than 0.04; Fisher's exact test). The number of children who died with multiple- and single-copy N-myc gene was 4/4 and 5/9 respectively (p greater than 0.05; Chi-squared test). There was no statistically significant correlation between N-myc amplification and age, gender, site, stage or survival time. There was no amplification or gross rearrangement of c-myc in any of the 13 RMS.