<b><i>Background/Aims:</i></b> The porphyrias are genetically heterogeneous diseases, and each mutation is exclusive to one or two families. Among the mutations responsible for variegate porphyria in our country, c.1042_1043insT stands out, since it was described only in Argentina and is present in about 40% of genetically diagnosed families. Thus, we hypothesized the possible existence of a common ancestor for the mutation in our population. <b><i>Methods:</i></b> We conducted a study based on microsatellite (short tandem repeats) haplotypes. <b><i>Results:</i></b> We found a common haplotype in all of the patients carrying the common mutation. The age of the mutation was estimated to be about 375 years. <b><i>Conclusion:</i></b> There is a recent founder effect in our population for this particular genetic alteration in variegate porphyria.