We studied a three-generation pedigree in which seven individuals were affected by aplasia cutis congenita, a rare disorder characterized by the congenital absence of the epidermis, dermis and subcutaneous tissue of the vertex or occipital region. Accurate clinical and formal genetic analysis suggested that this family was affected by the autosomal dominant form of the disease, a hereditary condition due to mutations of an unknown gene. To define the map position of this locus, we performed linkage analysis on candidate chromosomes (long arm of chromosomes 1 and 12). Negative lod scores were obtained for all markers analysed and linkage with genes located in these chromosomal regions was excluded.