“…Eight clusters involved only women [Li et al, 1978;Vianna and Polan, 1978;Munoz et al, 1988;Dawson et al, 1992;Ascoli et al, 1998;Bisconti et al, 2000;Musti et al, 2002;Bianchi et al, 2004;Serio et al, 2004]. All clusters included first-degree relatives and three of them involved also second-degree relatives [Li et al, 1989;Precerutti et al, 1990;Ascoli et al, 1998]. Only one cluster with heavy exposure involved the triple relationship mother, father and son [Otte et al, 1990].…”