45, X/46, XX Mosaicism in a Mother and One of Her Discordant Monozygotic Twin Daughters: Report of One Case

45,X/46,XX鑲嵌型透納氏症：一對母女之病例報告

10.7097/APT.200610.0252

蘇本華(Pen-Hua Su)；陳家玉(Jia-Yuh Chen)；陳素珍(Suh-Jen Chen)；洪惠媚(Huei-Mei Hung)；丁鴻志(Hung-Chih Ting)；林靜儀(Ching-Yi Lin)；郭業文(Yeak-Wen Quek)

45,X/46,XX mosaicism ； Turner syndrome ； monozygotic twin ； discordant

Acta Paediatrica Taiwanica

47卷5期（2006 / 10 / 01）

252 - 254

英文

Decreased fertility is one of the characteristics of Turner syndrome. Ovarian function in women with Turner syndrome is believed to be impaired because of an abnormal and very rapid maturation of oocytes and follicles. About 30% of mosaic Turner patients have partial ovarian function during puberty, but only 2-5% of them will ever become pregnant. We describe a woman with a mosaic form of Turner syndrome (45,X [6]/46,XX [94] karyotype from blood lymphocytes), who had a spontaneous puberty and normal fertility. After her second pregnancy, she gave birth to a set of monozygotic female twins; Twin B presented with a mild Turner syndrome phenotype and Twin A with a normal female phenotype. Karyotypic analysis performed on amniotic fluid and fetal blood samples demonstrated a normal 46,XX chromosome constitution in Twin A and a 45,X/46,XX mosaicism (27%:73% for amniotic fluid and 6%:94% for fetal blood) in Twin B. Postnatal cytogenetic investigation of blood lymphocytes showed the 45,X [7]/46,XX [93] mosaicism in Twin B. Further investigations of blood lymphocytes in both girls at the age of 4 years showed Twin A with a 46,XX karyotype and Twin B with a 45,X [4]/46,XX [96] mosaicism. The phenotype of twin A had a normal appearance, but webbing of the neck, low posterior hair line, shield chest, and mild psychomotor retardation were evident in Twin B.