Abstract:

[Abstract] Objective Clonality of keratoacanthoma(KA) was analyzed by means of the polymerase chain reaction（PCR）. Methods Genomic DNA was extracted from archival formalin-fixed, paraffin-embedded tissues and digested through incubation with HpaII and amplified through PCR for a portion of the X-chromosome-linked phosphoglycerate kinase(PGK) gene. The products were treated with BstXI and resolved on agarose gels. Results Amplification was successful in 5 of 11 cases of KA. 3 cases were heterozygous for the BstXI polymorphic site of the PGK amplified product, permitting analysis of clonality. A monoclonal pattern of X-chromosome inactivation was found in 3 informative cases. Conclution PCR amplification can be used for the determination of the pattern of X-chromosome inactivation in formalin-fixed tissues. Such an approach makes it feasible to include specimens from archival tissue collections in the analysis of clonality. KA is of clonal origin.

Key words: [Key word] Keratoacanthoma, Clonality, X chromosome inactivation, phosphoglycerate kinase