Giardia duodenalis carries out canonical homologous recombination and single-strand annealing.

In the past decades, the ability of Giardia duodenalis to perform homologous recombination has been suggested, supported by the observations of genomic integration of foreign plasmids and the disruption of genes using CRISPR technology. Unfortunately, the direct study of a HR mechanism has not been addressed, which would be pertinent in a minimalist organism lacking fundamental DNA-repair elements and even complete pathways. In addition, the constant ploidy changes through the life cycle of this parasite highlight the conservation and relevance of homologous recombination in maintaining genomic stability.