previous biochemical studies have suggested that both x chromosomes produce gene products when cells of the lt-1 teratocarcinoma stem cell line are maintained in the undifferentiated state , and that dosage compensation , the biochemical manifestation of x inactivation , occurs when the cells are induced to differentiate in vitro ( martin et al. , 1978 ) .
C0043292
x chromosomes
C0043297
x inactivation