Alternative splicing is a common natural tool for the inhibition of function of full length gene products. We explored whether there was evidence that alternative splicing of ERCC1 may serve such a function for nucleotide excision repair. The ratio of alternatively spliced species to full length species was assessed for the protein and/or for the mRNA, for a series of human cell lines and tissues. This ratio was plotted against the amount of cisplatin-DNA adduct repair in each cell line (n=9), as measured by atomic absorbance spectrometry. As the percentage of alternatively spliced protein and/or mRNA increased, the amount of cisplatin-DNA adduct that was repaired was reduced. This inverse relationship was associated with a substantial amount of scatter (r=0.635), particularly at low levels of repair. These data demonstrate an association between alternative splicing of ERCC1, and reduction in cellular capability to repair cisplatin-DNA adduct.