“…According to several authors, the percentage of the aneuploid cell line would be determinant for a patient carrying a ring chromosome to assess his fertility and phenotype (Wegner et al, 1992;Pezzolo et al, 1993a;Hsu et al, 1994;Henegariu et al, 1997a;Tzancheva et al, 1999). The frequencies of the cell line without the r(Y) in father and son in interphase cells ranged from 12 to 20%, corresponding to the lower percentages obtained by other authors in similar studies (ranging from 5 to 85%) (Chandley and Edmond, 1971;Maeda et al, 1976;Taillemite et al, 1978;Steinbach et al, 1979;Kosztola ´nyi, 1988;Micic et al, 1990;Wegner et al, 1992;Hsu, 1994;Henegariu et al, 1997a;Bofinger et al, 1999;Tzancheva et al, 1999;Blanco et al, 2003).…”