Chromosome 16p deletion

Alternate names

Deletion 16p; Monosomy 16p; 16p deletion; 16p monosomy

Definition

Chromosome 16p deletion is a chromosome abnormality that occurs when there is a missing (deleted) copy of genetic material on the short arm (p) of chromosome 16.

1 deletion, 2 duplication and 3 inversion.

Deletion of chromosome section

Cause

This condition occurs when there is a missing (deleted) copy of genetic material on the short arm (p) of chromosome 16.

Inheritance

• 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 deletion.

Signs and symptoms

• The severity of the condition and the signs and symptoms depend on the size and location of the deletion and which genes are involved. Features that often occur in people with chromosome 16p deletion 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 16p deletion

Chromosome 16p deletion is a rare disease.