“…To integrate the findings of the present study and the descriptions in the literature, a pathogenesis is hypothesized in INTRODUCTION Cystic hyrgoma of the neck is a congenital malformation with cystic dilatation of the lymphatic system often progressing to hydrops fetalis [Chervenak et al, 19831. After an observation of aborted 45,X fetuses by Singh and Carr [1966], cystic hygromas of the neck were thought to be an intrauterine manifestation of the web neck in Ullrich-Turner syndrome (UTS). With the recent technical progress of prenatal detection by ultrasonography, cystic hyrgromas have been reported in many other aneuploids such as trisomy 13 [Greenberg et al, 19 83;Nakazato et al, 19853, trisomy 18, trisomy 21 [Pearce et al, 1984;Redford et al, 19841, dup(l1p) [Fryns et al, 19851; in polyploidy 90,XX [Fryns et al, 19871; and single gene disorders such as Noonan syndrome [Witt et al, 19871 and Robert syndrome [Graham et al, 19831 have been reported. Similar lesions were recently confirmed in mice with chromosome abnormality [Miyabara, 19891. These reports of human cases provided a chance to consider the cause, natural history, and significance of this abnormality [Chervenak et al, 1983;Byrne et al, 19841.…”