Sequence analysis of ILK mRNA and gene in mutant cells. (A) Analysis of ILK mRNA sequence. ILK mRNA of parental cells and mutant cells was amplified by RT-PCR and the PCR products were directly sequenced. Two different nonsense mutations R317X and W383X were identified in the ILK kinase domain in the mutant cells in a heterozygous state. (B) Analysis of the Ilk gene sequence. The 895-bp region encompassing exon 9 through exon 12 in the Ilk gene was amplified by PCR. The PCR products were subcloned into pCR4-TOPO vector and sequenced. The vector inserts included one or the other mutation.