The evolutionary history of HSA7/16 synteny in vertebrates: a critical interpretation of comparative cytogenetic and genome sequence data

The current work is an in silico study of data from previous publications and genome browsers, on the origin of the human synteny HSA7a/16p. The molecular composition of the chromosomal segments identified as HSA7a/16 and 7b (free or differently associated) is not yet clear. This means that a syntenic association 7/16, which can be detected by an in situ hybridization (FISH) method in different taxa, may not necessarily correspond to those of the same association in different lineages. In silico research, together with comparative cytogenetics, have been applied in order to define the composition of the 7/16 syntenic association. These results allow a confident reconstruction of the syntenic associations HSA7/16 in diverse vertebrate lineages, indicating various levels of homology, but also considerable levels of non-homology, which should elicit caution with phylogenetic interpretations. The 7/16 association represents a paradigmatic example of the complexity involved in the interpretation of comparative cytogenetic data from a phylogenetic perspective.