All issues > Volume 45(7); 2002

Case Report

J Korean Pediatr Soc. 2002;45(7):917-922. Published online July 15, 2002.

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

Saeah S Min¹, Seonwoong SW Lim¹, Youngsook YS Kim², Ohkyung OK Lee¹

¹Department of Pediatrics, Presbyterian Medical Center, Chonju, Korea
²Department of Clinical Pathology, Presbyterian Medical Center, Chonju, Korea

Correspondence Ohkyung OK Lee ,Email: okleepmc@netian.com

Abstract

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.

Keywords :Unbalanced translocation, Chromosome 2, Chromosome 7