Extra G-Positive Band at Chromosome 9Q13 As a Recurrent Heteromorphism in a Korean Population

Abstract

The extra G-positive, C-negative band within 9q13 has been repeatedly found during chromosomal analyses of amniocenteses with a frequency of 2.4 in 1000 (28 cases in 11,890 chromosomal analyses) in the Korean population. All of the carrier parents with this variant did not have any phenotypic abnormalities and 10 cases that were followed after birth showed that all, except 1 patient with duodenal atresia, had no apparent phenotypic abnormalities. The results of Agilent 244 K oligonucleotide array CGH showed no changes of genomic dosages. We can be sure that the extra bands present are heterochromatic materials of no clinical significance.

Keywords :

• array CGH
• heterochromatin
• polymorphism