A Rare Chromosome 3 Imbalance and Its Clinical Implications

Abstract EN

The duplication of chromosome 3q is a rare disorder with varying chromosomal breakpoints and consequently symptoms.

Even rarer is the unbalanced outcome from a parental inv(3) resulting in duplicated 3q and a deletion of 3p.

Molecular karyotyping should aid in precisely determining the length and breakpoints of the 3q+/3p− so as to better understand a child’s future development and needs.

We report a case of an infant male with a 57.5 Mb duplication from 3q23-qter.

This patient also has an accompanying 1.7 Mb deletion of 3p26.3.

The duplicated segment in this patient encompasses the known critical region of 3q26.3-q27, which is implicated in the previously reported 3q dup syndrome; however, the accompanying 3p26.3 deletion is smaller than the previously reported cases.

The clinical phenotype of this patient relates to previously reported cases of 3q+ that may suggest that the accompanying 1.7 Mb heterozygous deletion is not clinically relevant.

Taken together, our data has refined the location and extent of the chromosome 3 imbalance, which will aid in better understanding the molecular underpinning of the 3q syndrome.