Chromosome 13q duplication

Alternate names

Duplication 13q; Trisomy 13q; 13q duplication; 13q trisomy; Partial trisomy 13q

Definition

Chromosome 13q duplication is a chromosome abnormality that occurs when there is an extra (duplicated) copy of genetic material on the long arm (q) of chromosome 13.

Cause

This condition occurs when there is an extra (duplicated) copy of genetic material on the long arm (q) of chromosome 13.

Inheritance

• Chromosome testing of both parents can provide more information on whether or not the duplication was inherited.
• In most cases, parents do not have any chromosomal anomaly.
• However, sometimes one parent is found to have a balanced translocation, where a piece of a chromosome has broken off and attached to another one with no gain or loss of genetic material.
• The balanced translocation normally does not cause any signs or symptoms, but it increases the risk for having an affected child with a chromosomal anomaly like a duplication.

Signs and symptoms

• The severity of the condition and the signs and symptoms depend on the size and location of the duplication and which genes are involved. Features that often occur in people with chromosome 13q duplication include developmental delay, intellectual disability, behavioral problems and distinctive facial features.

Diagnosis

Chromosome disorders may be suspected in people who have developmental delays, intellectual disabilities and/or physical abnormalities.

Several types of genetic tests can identify chromosome disorders:

• Karyotype - a karyotype is a laboratory test that produces an image of a person's chromosomes. This test can be used to diagnose large deletions.
• FISH - a laboratory technique that is used to detect and locate a specific DNA sequence on a chromosome. During FISH, a chromosome is exposed to a small DNA sequence called a probe that has a fluorescent molecule attached to it. The probe sequence binds to its corresponding sequence on the chromosome. This test can be used in combination with karyotyping for deletions that are too small to be seen on karyotype, alone. However, FISH is only useful if the person ordering the test suspects there is a deletion of a specific region of 4q.
• Array CGH - a technology that detects deletions that are too small to be seen on karyotype.

Treatment

Treatment is based on the signs and symptoms present in each person.

NIH genetic and rare disease info

• NIH info on Chromosome 13q duplication

Chromosome 13q duplication is a rare disease.