“…From a literature review of around 30 voice-related twin studies (San Segundo, 2014), we can draw some interesting conclusions. For instance, it seems that previous phonetic studies focusing on twins have aimed at basically one of the following objectives (see San Segundo, 2015): (a) trying to find a genetic component in the variation of certain voice characteristics by searching differences between MZ and DZ twin pairs (e.g., Debruyne, Decoster, Van Gijsel, & Vercammen, 2002;Przybyla, Horii, & Crawford, 1992) or else, in a forensic scenario, (b) creating a system capable of discriminating between MZ and DZ twins (e.g., Forrai & Gordos, 1983) or, more frequently, testing whether it is possible to distinguish a speaker from his/her co-twin (e.g., Ariyaeeinia, Morrison, Malegaonkar, & Black, 2008;Homayounpour & Chollet, 1995;Künzel, 2010;Loakes, 2006;Nolan & Oh, 1996;Scheffer, Bonastre, Ghio, & Teston 2004). For a thorough discussion of the results derived from previous twin studies, see San Segundo (2014), where previous works have been classified in four groups depending on whether they represent perceptual, acoustic, articulatory or automatic (ASR) approaches.…”