7号染色体臂间倒位伴Turner综合征家系分析

目的研究7号染色体臂间倒位的遗传机制.方法患儿及父母作染色体检查,并对患儿的家系进行调查.结果患儿的染色体核型为46,XX,inv(7)(p22q11)/45,X,inv(7)(p22q11),其中46,XX,inv(7)(p2q11),85%,45,X,inv(7)(p22q11),15%.父亲的核型为46,XY,inv(7)(p22q11),母亲的染色体正常,患儿的母亲第1胎为3月自然流产,家系中其他成员均无流产史,母系成员中身材均偏矮小.结论染色体臂间倒位能引起流产和畸胎,应作产前诊断.

Analysis of pericentric inversion of chromosome 7 associated with Turner syndrome in family

Objective:To investigate the genetic mechanism of pericentric inversion of chromosome 7. Methods:The patient and her parents were chromosome karyotype analysed. Results: Cytogenetic evaluation by G banding a pericentric inversion of chromosome 7 and mosaic Turner syndrome,45,XO/46,XX,inv (7)(p22q11).The position of the centromeres was identified by the CBG technique.One hundred metaphases were counted with 45,XO,inv(7) in 15% and 46,XX, inv(7)in 85%.A family study revealed the same abnormal inversion in her father while the mother was normal .But her mother had short stature .Her father's karyotypeJP] was 46,XY, inv(7)(p22q11).The inversion was paternal.This mother with miscarriage for her first pregnancy at 12 weeks gestation may be related to the consequence of unbalanced gamete. Conclusion: Amniocytic cytogenetic examinate should be indispensable for prenatal diagnosis and terminating pregnancy is suggested when the foetus is found with unbalanced inversion karyotype.