Turner's syndrome in monozygotic twins.

The clinical picture of short stature, neck webbing, and cubitus valgus was first described by Ulirich (1930) in males and females with normal pubertal development. In his classical description, Turner (I938) described a similar clinical picture in females who had primary amenorrhoea. Since the original description, numerous contributions have been made to the study of this syndrome: sex chromatin was found to be absent (Polani, Hunter, and Lennox, I954; Wilkins, Grumbach, and Van Wyk, 1954), and subsequently it was discovered that there was a missing X chromosome (Ford, Jones, Polani, de Almeida, and Briggs, I959). It is now known that there can be various chromosome mosaic patterns in association with both chromatin negative and positive patients (Polani, i96i), and this author mentions that the clinical features of the syndrome may be found in men and women who have normal chromosomes. It is interesting to note that in his original description in I938 Turner described twin girls aged i6 years, one of whom showed the typical features of the syndrome, while her twin was apparently normal, the menarche having been established at the age of I2 years. 24 years later he described twins of proven monozygosity concordant for the syndrome, each having an XO chromosomal pattern (Turner and Zanartu, i962), and there have been several reports of the syndrome in one or both of monozygotic and dizygotic twins (Table I). We wish to report a further pair of discordant monozygotic twins: they are of particular interest because of associated abnormalities, necropsy findings, and Xg blood grouping. of gestation at the Horton Maternity Hospital, Banbury, after a normal pregnancy. The first baby weighed 4 lb. 5 OZ. (I956 g.) and was delivered as a vertex; the cord was wound three times round the neck and regular respirations were not established for I2 minutes. The second baby weighed 6 lb. 2 oz. (2777 g.) and was an assisted breech delivery; she cried well at birth and no abnormality was apparent on clinical examination. Reviewed at 6 months, she appeared to be developing normally. The placenta was reported as single but was not available for detailed examination. The first babyshowednumerous abnormalities (Fig. i); the face was rather small, the skin dry with little subcutaneous fat. A large omphalocele was present,