Folate deficiency induced premature signs of hearing loss in both strains, although their appearance is delayed more than 6 months in the CBA/Ca strain as compared to C57BL/6J mice (Martinez-Vega et al., 2015a). Moreover, the extent of the damage is also very different, since most C57BL/6J mice showed profound hearing loss after 2 months on the FD diet (Martinez-Vega et al., 2015a), whereas the changes in hearing parameters in CBA/Ca mice are small, but consistent (increased DP thresholds and 2f1-f2 amplitude) and appear after 8 months on the deficient diet. In fact, histological data corroborated cochlear damage in CBA/Ca mice that was more evident in the FD animals. Folate-induced damage seemed restricted to the low basal turn of the cochlea, thus explaining that stimulation required high frequency sounds (Müller et al., 2005). This higher resistance of the CBA/Ca cochleae against vitamin deficiency may rely in differences in the genetic background of the strains used that remain largely unknown (Willott et al., 1995).