Unbalanced Translocations of Chromosome 2 and Chromosome 20 in a Two-Generation Family

2대에 걸쳐 나타난 염색체 2번과 20번의 비균형적 전위 1례

An unbalanced translocation is frequently the result of inheritance of an unbalanced haploid set from a parent with a balanced translocation. Families in which one parent is a balanced translocation carrier fall into the following classes : Those in which none of the possible abnormal offsprings is viable; Those in which one type of offspring, usually the one with the smaller deletion, is born alive; Those in which two types of abnormal offspring are viable. We report a neonate whose karyotype was 46,XX,der(2)t(2;7)(q21;p21.2),der(20)t(2;20)(q21;p13). She was small for her gestational age and had multiple anomalies such as exophthalmos, corneal opacity, short neck, tongue tie, clinodactyly, atrial septal defect, patent ductus arteriosus and ventriculomegaly. Moreover, her mother's karyotype was 46,XX,der(2)t(2;7)(q21;p21.2),del(16)(q22.1),der(20)t(2;20)(q21;p13) but her father had normal karyotype. The same derivative chrosomes were found between mother and her infant, except for del(16)(q22.1) in her mother and these same unbalanced translocations in a two-generation family are extremely rare.

저자들은 안구돌출, 각막혼탁, 혀 유착증, 짧은 목, 뇌실 확장, 심방중격결손증, 동맥관개존증 및 양측 다섯번째 중위지골이 짧은 증상을 갖은 선천성 이상 환아에서 세포 유전학 검사를 통해 2번과 7번의 비균형 전위로 인한 7번 염색체의 부분 삼체성, 2번과 20번의 비균형 전위가 모친에 의해 유전되어 나타났음을 경험하였기에 보고하는 바이다.