The authors describe a case of « situs viscerum inversus totalis » in two DZ twin-sisters.
They debate, on the basis of the elements in their possession, whether they have to do with DZ or MZ twin-sisters, and declare in favour of the former hypothesis. Accordingly, this is the fifth case described of such anomaly in twins, after the cases of Reinhardt, Pezzi and Carugati, Boccia and Maglione, Kean, and it is the first case in DZ twins.
The authors think the case described will contribute in winning for DZ twinship an acknowledgement of real twinship, according to Gedda's statements.